diff --git a/src/browser/Terminal.test.ts b/src/browser/Terminal.test.ts
index ba2ce6dd5..c651c248a 100644
--- a/src/browser/Terminal.test.ts
+++ b/src/browser/Terminal.test.ts
@@ -8,7 +8,7 @@ import type { IBrowser } from 'browser/Types';
 import { assert } from 'chai';
 import { DEFAULT_ATTR_DATA } from 'common/buffer/BufferLine';
 import { CellData } from 'common/buffer/CellData';
-import { MockUnicodeService } from 'common/TestUtils.test';
+import { MockUnicodeService, createCellData } from 'common/TestUtils.test';
 import { IMarker } from 'common/Types';
 
 const INIT_COLS = 80;
@@ -440,8 +440,8 @@ describe('Terminal', () => {
     describe('scroll() function', () => {
       describe('when scrollback > 0', () => {
         it('should create a new line and scroll', () => {
-          term.buffer.lines.get(0)!.setCell(0, CellData.fromCharData([0, 'a', 0, 'a'.charCodeAt(0)]));
-          term.buffer.lines.get(INIT_ROWS - 1)!.setCell(0, CellData.fromCharData([0, 'b', 0, 'b'.charCodeAt(0)]));
+          term.buffer.lines.get(0)!.setCell(0, createCellData(0, 'a', 0));
+          term.buffer.lines.get(INIT_ROWS - 1)!.setCell(0, createCellData(0, 'b', 0));
           term.buffer.y = INIT_ROWS - 1; // Move cursor to last line
           term.scroll(DEFAULT_ATTR_DATA.clone());
           assert.equal(term.buffer.lines.length, INIT_ROWS + 1);
@@ -451,9 +451,9 @@ describe('Terminal', () => {
         });
 
         it('should properly scroll inside a scroll region (scrollTop set)', () => {
-          term.buffer.lines.get(0)!.setCell(0, CellData.fromCharData([0, 'a', 0, 'a'.charCodeAt(0)]));
-          term.buffer.lines.get(1)!.setCell(0, CellData.fromCharData([0, 'b', 0, 'b'.charCodeAt(0)]));
-          term.buffer.lines.get(2)!.setCell(0, CellData.fromCharData([0, 'c', 0, 'c'.charCodeAt(0)]));
+          term.buffer.lines.get(0)!.setCell(0, createCellData(0, 'a', 0));
+          term.buffer.lines.get(1)!.setCell(0, createCellData(0, 'b', 0));
+          term.buffer.lines.get(2)!.setCell(0, createCellData(0, 'c', 0));
           term.buffer.y = INIT_ROWS - 1; // Move cursor to last line
           term.buffer.scrollTop = 1;
           term.scroll(DEFAULT_ATTR_DATA.clone());
@@ -463,11 +463,11 @@ describe('Terminal', () => {
         });
 
         it('should properly scroll inside a scroll region (scrollBottom set)', () => {
-          term.buffer.lines.get(0)!.setCell(0, CellData.fromCharData([0, 'a', 0, 'a'.charCodeAt(0)]));
-          term.buffer.lines.get(1)!.setCell(0, CellData.fromCharData([0, 'b', 0, 'b'.charCodeAt(0)]));
-          term.buffer.lines.get(2)!.setCell(0, CellData.fromCharData([0, 'c', 0, 'c'.charCodeAt(0)]));
-          term.buffer.lines.get(3)!.setCell(0, CellData.fromCharData([0, 'd', 0, 'd'.charCodeAt(0)]));
-          term.buffer.lines.get(4)!.setCell(0, CellData.fromCharData([0, 'e', 0, 'e'.charCodeAt(0)]));
+          term.buffer.lines.get(0)!.setCell(0, createCellData(0, 'a', 0));
+          term.buffer.lines.get(1)!.setCell(0, createCellData(0, 'b', 0));
+          term.buffer.lines.get(2)!.setCell(0, createCellData(0, 'c', 0));
+          term.buffer.lines.get(3)!.setCell(0, createCellData(0, 'd', 0));
+          term.buffer.lines.get(4)!.setCell(0, createCellData(0, 'e', 0));
           term.buffer.y = 3;
           term.buffer.scrollBottom = 3;
           term.scroll(DEFAULT_ATTR_DATA.clone());
@@ -481,11 +481,11 @@ describe('Terminal', () => {
         });
 
         it('should properly scroll inside a scroll region (scrollTop and scrollBottom set)', () => {
-          term.buffer.lines.get(0)!.setCell(0, CellData.fromCharData([0, 'a', 0, 'a'.charCodeAt(0)]));
-          term.buffer.lines.get(1)!.setCell(0, CellData.fromCharData([0, 'b', 0, 'b'.charCodeAt(0)]));
-          term.buffer.lines.get(2)!.setCell(0, CellData.fromCharData([0, 'c', 0, 'c'.charCodeAt(0)]));
-          term.buffer.lines.get(3)!.setCell(0, CellData.fromCharData([0, 'd', 0, 'd'.charCodeAt(0)]));
-          term.buffer.lines.get(4)!.setCell(0, CellData.fromCharData([0, 'e', 0, 'e'.charCodeAt(0)]));
+          term.buffer.lines.get(0)!.setCell(0, createCellData(0, 'a', 0));
+          term.buffer.lines.get(1)!.setCell(0, createCellData(0, 'b', 0));
+          term.buffer.lines.get(2)!.setCell(0, createCellData(0, 'c', 0));
+          term.buffer.lines.get(3)!.setCell(0, createCellData(0, 'd', 0));
+          term.buffer.lines.get(4)!.setCell(0, createCellData(0, 'e', 0));
           term.buffer.y = INIT_ROWS - 1; // Move cursor to last line
           term.buffer.scrollTop = 1;
           term.buffer.scrollBottom = 3;
@@ -506,9 +506,9 @@ describe('Terminal', () => {
         });
 
         it('should create a new line and shift everything up', () => {
-          term.buffer.lines.get(0)!.setCell(0, CellData.fromCharData([0, 'a', 0, 'a'.charCodeAt(0)]));
-          term.buffer.lines.get(1)!.setCell(0, CellData.fromCharData([0, 'b', 0, 'b'.charCodeAt(0)]));
-          term.buffer.lines.get(INIT_ROWS - 1)!.setCell(0, CellData.fromCharData([0, 'c', 0, 'c'.charCodeAt(0)]));
+          term.buffer.lines.get(0)!.setCell(0, createCellData(0, 'a', 0));
+          term.buffer.lines.get(1)!.setCell(0, createCellData(0, 'b', 0));
+          term.buffer.lines.get(INIT_ROWS - 1)!.setCell(0, createCellData(0, 'c', 0));
           term.buffer.y = INIT_ROWS - 1; // Move cursor to last line
           assert.equal(term.buffer.lines.length, INIT_ROWS);
           term.scroll(DEFAULT_ATTR_DATA.clone());
@@ -521,9 +521,9 @@ describe('Terminal', () => {
         });
 
         it('should properly scroll inside a scroll region (scrollTop set)', () => {
-          term.buffer.lines.get(0)!.setCell(0, CellData.fromCharData([0, 'a', 0, 'a'.charCodeAt(0)]));
-          term.buffer.lines.get(1)!.setCell(0, CellData.fromCharData([0, 'b', 0, 'b'.charCodeAt(0)]));
-          term.buffer.lines.get(2)!.setCell(0, CellData.fromCharData([0, 'c', 0, 'c'.charCodeAt(0)]));
+          term.buffer.lines.get(0)!.setCell(0, createCellData(0, 'a', 0));
+          term.buffer.lines.get(1)!.setCell(0, createCellData(0, 'b', 0));
+          term.buffer.lines.get(2)!.setCell(0, createCellData(0, 'c', 0));
           term.buffer.y = INIT_ROWS - 1; // Move cursor to last line
           term.buffer.scrollTop = 1;
           term.scroll(DEFAULT_ATTR_DATA.clone());
@@ -533,11 +533,11 @@ describe('Terminal', () => {
         });
 
         it('should properly scroll inside a scroll region (scrollBottom set)', () => {
-          term.buffer.lines.get(0)!.setCell(0, CellData.fromCharData([0, 'a', 0, 'a'.charCodeAt(0)]));
-          term.buffer.lines.get(1)!.setCell(0, CellData.fromCharData([0, 'b', 0, 'b'.charCodeAt(0)]));
-          term.buffer.lines.get(2)!.setCell(0, CellData.fromCharData([0, 'c', 0, 'c'.charCodeAt(0)]));
-          term.buffer.lines.get(3)!.setCell(0, CellData.fromCharData([0, 'd', 0, 'd'.charCodeAt(0)]));
-          term.buffer.lines.get(4)!.setCell(0, CellData.fromCharData([0, 'e', 0, 'e'.charCodeAt(0)]));
+          term.buffer.lines.get(0)!.setCell(0, createCellData(0, 'a', 0));
+          term.buffer.lines.get(1)!.setCell(0, createCellData(0, 'b', 0));
+          term.buffer.lines.get(2)!.setCell(0, createCellData(0, 'c', 0));
+          term.buffer.lines.get(3)!.setCell(0, createCellData(0, 'd', 0));
+          term.buffer.lines.get(4)!.setCell(0, createCellData(0, 'e', 0));
           term.buffer.y = 3;
           term.buffer.scrollBottom = 3;
           term.scroll(DEFAULT_ATTR_DATA.clone());
@@ -550,11 +550,11 @@ describe('Terminal', () => {
         });
 
         it('should properly scroll inside a scroll region (scrollTop and scrollBottom set)', () => {
-          term.buffer.lines.get(0)!.setCell(0, CellData.fromCharData([0, 'a', 0, 'a'.charCodeAt(0)]));
-          term.buffer.lines.get(1)!.setCell(0, CellData.fromCharData([0, 'b', 0, 'b'.charCodeAt(0)]));
-          term.buffer.lines.get(2)!.setCell(0, CellData.fromCharData([0, 'c', 0, 'c'.charCodeAt(0)]));
-          term.buffer.lines.get(3)!.setCell(0, CellData.fromCharData([0, 'd', 0, 'd'.charCodeAt(0)]));
-          term.buffer.lines.get(4)!.setCell(0, CellData.fromCharData([0, 'e', 0, 'e'.charCodeAt(0)]));
+          term.buffer.lines.get(0)!.setCell(0, createCellData(0, 'a', 0));
+          term.buffer.lines.get(1)!.setCell(0, createCellData(0, 'b', 0));
+          term.buffer.lines.get(2)!.setCell(0, createCellData(0, 'c', 0));
+          term.buffer.lines.get(3)!.setCell(0, createCellData(0, 'd', 0));
+          term.buffer.lines.get(4)!.setCell(0, createCellData(0, 'e', 0));
           term.buffer.y = INIT_ROWS - 1; // Move cursor to last line
           term.buffer.scrollTop = 1;
           term.buffer.scrollBottom = 3;
diff --git a/src/browser/renderer/dom/DomRendererRowFactory.test.ts b/src/browser/renderer/dom/DomRendererRowFactory.test.ts
index b6f6eedca..05fc8000c 100644
--- a/src/browser/renderer/dom/DomRendererRowFactory.test.ts
+++ b/src/browser/renderer/dom/DomRendererRowFactory.test.ts
@@ -10,7 +10,7 @@ import { NULL_CELL_CODE, NULL_CELL_WIDTH, NULL_CELL_CHAR, DEFAULT_ATTR, FgFlags,
 import { BufferLine, DEFAULT_ATTR_DATA } from 'common/buffer/BufferLine';
 import { IBufferLine } from 'common/Types';
 import { CellData } from 'common/buffer/CellData';
-import { MockCoreService, MockDecorationService, MockOptionsService } from 'common/TestUtils.test';
+import { MockCoreService, MockDecorationService, MockOptionsService, createCellData, NULL_CELL_DATA } from 'common/TestUtils.test';
 import { MockCharacterJoinerService, MockCoreBrowserService, MockThemeService } from 'browser/TestUtils.test';
 import { TestWidthCache } from 'browser/renderer/dom/WidthCache.test';
 
@@ -48,9 +48,9 @@ describe('DomRendererRowFactory', () => {
 
     it('should set correct attributes for double width characters', () => {
       widthCache.setWidths({ '語': 10 });
-      lineData.setCell(0, CellData.fromCharData([DEFAULT_ATTR, '語', 2, '語'.charCodeAt(0)]));
+      lineData.setCell(0, createCellData(DEFAULT_ATTR, '語', 2));
       // There should be no element for the following "empty" cell
-      lineData.setCell(1, CellData.fromCharData([DEFAULT_ATTR, '', 0, 0]));
+      lineData.setCell(1, createCellData(DEFAULT_ATTR, '', 0));
       const spans = rowFactory.createRow(lineData, 0, false, undefined, undefined, 0, false, true, 5, widthCache, -1, -1);
       assert.equal(extractHtml(spans),
         '<span>語</span>'
@@ -117,7 +117,7 @@ describe('DomRendererRowFactory', () => {
 
     describe('attributes', () => {
       it('should add class for bold', () => {
-        const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+        const cell = createCellData(0, 'a', 1);
         cell.fg = DEFAULT_ATTR_DATA.fg | FgFlags.BOLD;
         lineData.setCell(0, cell);
         const spans = rowFactory.createRow(lineData, 0, false, undefined, undefined, 0, false, true, 5, widthCache, -1, -1);
@@ -127,7 +127,7 @@ describe('DomRendererRowFactory', () => {
       });
 
       it('should add class for italic', () => {
-        const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+        const cell = createCellData(0, 'a', 1);
         cell.bg = DEFAULT_ATTR_DATA.bg | BgFlags.ITALIC;
         lineData.setCell(0, cell);
         const spans = rowFactory.createRow(lineData, 0, false, undefined, undefined, 0, false, true, 5, widthCache, -1, -1);
@@ -137,7 +137,7 @@ describe('DomRendererRowFactory', () => {
       });
 
       it('should add class for dim', () => {
-        const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+        const cell = createCellData(0, 'a', 1);
         cell.bg = DEFAULT_ATTR_DATA.bg | BgFlags.DIM;
         lineData.setCell(0, cell);
         const spans = rowFactory.createRow(lineData, 0, false, undefined, undefined, 0, false, true, 5, widthCache, -1, -1);
@@ -148,7 +148,7 @@ describe('DomRendererRowFactory', () => {
 
       describe('underline', () => {
         it('should add class for straight underline style', () => {
-          const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+          const cell = createCellData(0, 'a', 1);
           cell.fg = DEFAULT_ATTR_DATA.fg | FgFlags.UNDERLINE;
           cell.bg = DEFAULT_ATTR_DATA.bg | BgFlags.HAS_EXTENDED;
           cell.extended.underlineStyle = UnderlineStyle.SINGLE;
@@ -159,7 +159,7 @@ describe('DomRendererRowFactory', () => {
           );
         });
         it('should add class for double underline style', () => {
-          const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+          const cell = createCellData(0, 'a', 1);
           cell.fg = DEFAULT_ATTR_DATA.fg | FgFlags.UNDERLINE;
           cell.bg = DEFAULT_ATTR_DATA.bg | BgFlags.HAS_EXTENDED;
           cell.extended.underlineStyle = UnderlineStyle.DOUBLE;
@@ -170,7 +170,7 @@ describe('DomRendererRowFactory', () => {
           );
         });
         it('should add class for curly underline style', () => {
-          const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+          const cell = createCellData(0, 'a', 1);
           cell.fg = DEFAULT_ATTR_DATA.fg | FgFlags.UNDERLINE;
           cell.bg = DEFAULT_ATTR_DATA.bg | BgFlags.HAS_EXTENDED;
           cell.extended.underlineStyle = UnderlineStyle.CURLY;
@@ -181,7 +181,7 @@ describe('DomRendererRowFactory', () => {
           );
         });
         it('should add class for double dotted style', () => {
-          const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+          const cell = createCellData(0, 'a', 1);
           cell.fg = DEFAULT_ATTR_DATA.fg | FgFlags.UNDERLINE;
           cell.bg = DEFAULT_ATTR_DATA.bg | BgFlags.HAS_EXTENDED;
           cell.extended.underlineStyle = UnderlineStyle.DOTTED;
@@ -192,7 +192,7 @@ describe('DomRendererRowFactory', () => {
           );
         });
         it('should add class for dashed underline style', () => {
-          const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+          const cell = createCellData(0, 'a', 1);
           cell.fg = DEFAULT_ATTR_DATA.fg | FgFlags.UNDERLINE;
           cell.bg = DEFAULT_ATTR_DATA.bg | BgFlags.HAS_EXTENDED;
           cell.extended.underlineStyle = UnderlineStyle.DASHED;
@@ -205,7 +205,7 @@ describe('DomRendererRowFactory', () => {
       });
 
       it('should add class for overline', () => {
-        const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+        const cell = createCellData(0, 'a', 1);
         cell.bg = DEFAULT_ATTR_DATA.bg | BgFlags.OVERLINE;
         lineData.setCell(0, cell);
         const spans = rowFactory.createRow(lineData, 0, false, undefined, undefined, 0, false, true, 5, widthCache, -1, -1);
@@ -215,7 +215,7 @@ describe('DomRendererRowFactory', () => {
       });
 
       it('should add class for strikethrough', () => {
-        const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+        const cell = createCellData(0, 'a', 1);
         cell.fg = DEFAULT_ATTR_DATA.fg | FgFlags.STRIKETHROUGH;
         lineData.setCell(0, cell);
         const spans = rowFactory.createRow(lineData, 0, false, undefined, undefined, 0, false, true, 5, widthCache, -1, -1);
@@ -225,7 +225,7 @@ describe('DomRendererRowFactory', () => {
       });
 
       it('should hide blinking text when blink is off', () => {
-        const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+        const cell = createCellData(0, 'a', 1);
         cell.fg = DEFAULT_ATTR_DATA.fg | FgFlags.BLINK | FgFlags.UNDERLINE;
         cell.bg = DEFAULT_ATTR_DATA.bg | BgFlags.HAS_EXTENDED;
         cell.extended.underlineStyle = UnderlineStyle.SINGLE;
@@ -241,7 +241,7 @@ describe('DomRendererRowFactory', () => {
       });
 
       it('should add classes for 256 foreground colors', () => {
-        const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+        const cell = createCellData(0, 'a', 1);
         cell.fg |= Attributes.CM_P256;
         for (let i = 0; i < 256; i++) {
           cell.fg &= ~Attributes.PCOLOR_MASK;
@@ -255,7 +255,7 @@ describe('DomRendererRowFactory', () => {
       });
 
       it('should add classes for 256 background colors', () => {
-        const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+        const cell = createCellData(0, 'a', 1);
         cell.bg |= Attributes.CM_P256;
         for (let i = 0; i < 256; i++) {
           cell.bg &= ~Attributes.PCOLOR_MASK;
@@ -269,7 +269,7 @@ describe('DomRendererRowFactory', () => {
       });
 
       it('should correctly invert colors', () => {
-        const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+        const cell = createCellData(0, 'a', 1);
         cell.fg |= Attributes.CM_P16 | 2 | FgFlags.INVERSE;
         cell.bg |= Attributes.CM_P16 | 1;
         lineData.setCell(0, cell);
@@ -280,7 +280,7 @@ describe('DomRendererRowFactory', () => {
       });
 
       it('should correctly invert default fg color', () => {
-        const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+        const cell = createCellData(0, 'a', 1);
         cell.fg |= FgFlags.INVERSE;
         cell.bg |= Attributes.CM_P16 | 1;
         lineData.setCell(0, cell);
@@ -291,7 +291,7 @@ describe('DomRendererRowFactory', () => {
       });
 
       it('should correctly invert default bg color', () => {
-        const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+        const cell = createCellData(0, 'a', 1);
         cell.fg |= Attributes.CM_P16 | 1 | FgFlags.INVERSE;
         lineData.setCell(0, cell);
         const spans = rowFactory.createRow(lineData, 0, false, undefined, undefined, 0, false, true, 5, widthCache, -1, -1);
@@ -301,7 +301,7 @@ describe('DomRendererRowFactory', () => {
       });
 
       it('should turn bold fg text bright', () => {
-        const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+        const cell = createCellData(0, 'a', 1);
         cell.fg |= FgFlags.BOLD | Attributes.CM_P16;
         for (let i = 0; i < 8; i++) {
           cell.fg &= ~Attributes.PCOLOR_MASK;
@@ -315,7 +315,7 @@ describe('DomRendererRowFactory', () => {
       });
 
       it('should set style attribute for RBG', () => {
-        const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+        const cell = createCellData(0, 'a', 1);
         cell.fg |= Attributes.CM_RGB | 1 << 16 | 2 << 8 | 3;
         cell.bg |= Attributes.CM_RGB | 4 << 16 | 5 << 8 | 6;
         lineData.setCell(0, cell);
@@ -326,7 +326,7 @@ describe('DomRendererRowFactory', () => {
       });
 
       it('should correctly invert RGB colors', () => {
-        const cell = CellData.fromCharData([0, 'a', 1, 'a'.charCodeAt(0)]);
+        const cell = createCellData(0, 'a', 1);
         cell.fg |= Attributes.CM_RGB | 1 << 16 | 2 << 8 | 3 | FgFlags.INVERSE;
         cell.bg |= Attributes.CM_RGB | 4 << 16 | 5 << 8 | 6;
         lineData.setCell(0, cell);
@@ -339,8 +339,8 @@ describe('DomRendererRowFactory', () => {
 
     describe('selectionForeground', () => {
       it('should force selected cells with content to be rendered above the background', () => {
-        lineData.setCell(0, CellData.fromCharData([DEFAULT_ATTR, 'a', 1, 'a'.charCodeAt(0)]));
-        lineData.setCell(1, CellData.fromCharData([DEFAULT_ATTR, 'b', 1, 'b'.charCodeAt(0)]));
+        lineData.setCell(0, createCellData(DEFAULT_ATTR, 'a', 1));
+        lineData.setCell(1, createCellData(DEFAULT_ATTR, 'b', 1));
         rowFactory.handleSelectionChanged([1, 0], [2, 0], false);
         const spans = rowFactory.createRow(lineData, 0, false, undefined, undefined, 0, false, true, 5, widthCache, -1, -1);
         assert.equal(extractHtml(spans),
@@ -348,7 +348,7 @@ describe('DomRendererRowFactory', () => {
         );
       });
       it('should force whitespace cells to be rendered above the background', () => {
-        lineData.setCell(1, CellData.fromCharData([DEFAULT_ATTR, 'a', 1, 'a'.charCodeAt(0)]));
+        lineData.setCell(1, createCellData(DEFAULT_ATTR, 'a', 1));
         rowFactory.handleSelectionChanged([0, 0], [2, 0], false);
         const spans = rowFactory.createRow(lineData, 0, false, undefined, undefined, 0, false, true, 5, widthCache, -1, -1);
         assert.equal(extractHtml(spans),
@@ -374,9 +374,9 @@ describe('DomRendererRowFactory', () => {
     });
 
     it('can merge codepoints for equal spacing', () => {
-      lineData.setCell(0, CellData.fromCharData([DEFAULT_ATTR, 'a', 1, 'a'.charCodeAt(0)]));
-      lineData.setCell(1, CellData.fromCharData([DEFAULT_ATTR, 'b', 1, 'b'.charCodeAt(0)]));
-      lineData.setCell(2, CellData.fromCharData([DEFAULT_ATTR, 'c', 1, 'c'.charCodeAt(0)]));
+      lineData.setCell(0, createCellData(DEFAULT_ATTR, 'a', 1));
+      lineData.setCell(1, createCellData(DEFAULT_ATTR, 'b', 1));
+      lineData.setCell(2, createCellData(DEFAULT_ATTR, 'c', 1));
       const spans = rowFactory.createRow(lineData, 0, false, undefined, undefined, 0, false, true, 5, widthCache, -1, -1);
       assert.equal(extractHtml(spans),
         '<span>abc</span>'
@@ -385,9 +385,9 @@ describe('DomRendererRowFactory', () => {
 
     it('should not merge codepoints with different spacing', () => {
       widthCache.setWidths({ '€': 2 });
-      lineData.setCell(0, CellData.fromCharData([DEFAULT_ATTR, 'a', 1, 'a'.charCodeAt(0)]));
-      lineData.setCell(1, CellData.fromCharData([DEFAULT_ATTR, '€', 1, '€'.charCodeAt(0)]));
-      lineData.setCell(2, CellData.fromCharData([DEFAULT_ATTR, 'c', 1, 'c'.charCodeAt(0)]));
+      lineData.setCell(0, createCellData(DEFAULT_ATTR, 'a', 1));
+      lineData.setCell(1, createCellData(DEFAULT_ATTR, '€', 1));
+      lineData.setCell(2, createCellData(DEFAULT_ATTR, 'c', 1));
       const spans = rowFactory.createRow(lineData, 0, false, undefined, undefined, 0, false, true, 5, widthCache, -1, -1);
       assert.equal(extractHtml(spans),
         '<span>a</span><span style="letter-spacing: 3px;">€</span><span>c</span>'
@@ -395,9 +395,9 @@ describe('DomRendererRowFactory', () => {
     });
 
     it('should not merge on FG change', () => {
-      const aColor1 = CellData.fromCharData([DEFAULT_ATTR, 'a', 1, 'a'.charCodeAt(0)]);
+      const aColor1 = createCellData(DEFAULT_ATTR, 'a', 1);
       aColor1.fg |= Attributes.CM_P16 | 1;
-      const bColor2 = CellData.fromCharData([DEFAULT_ATTR, 'b', 1, 'b'.charCodeAt(0)]);
+      const bColor2 = createCellData(DEFAULT_ATTR, 'b', 1);
       bColor2.fg |= Attributes.CM_P16 | 2;
       lineData.setCell(0, aColor1);
       lineData.setCell(1, aColor1);
@@ -410,11 +410,11 @@ describe('DomRendererRowFactory', () => {
     });
 
     it('should not merge cursor cell', () => {
-      lineData.setCell(0, CellData.fromCharData([DEFAULT_ATTR, 'a', 1, 'a'.charCodeAt(0)]));
-      lineData.setCell(1, CellData.fromCharData([DEFAULT_ATTR, 'a', 1, 'a'.charCodeAt(0)]));
-      lineData.setCell(2, CellData.fromCharData([DEFAULT_ATTR, 'X', 1, 'X'.charCodeAt(0)]));
-      lineData.setCell(3, CellData.fromCharData([DEFAULT_ATTR, 'b', 1, 'b'.charCodeAt(0)]));
-      lineData.setCell(4, CellData.fromCharData([DEFAULT_ATTR, 'b', 1, 'b'.charCodeAt(0)]));
+      lineData.setCell(0, createCellData(DEFAULT_ATTR, 'a', 1));
+      lineData.setCell(1, createCellData(DEFAULT_ATTR, 'a', 1));
+      lineData.setCell(2, createCellData(DEFAULT_ATTR, 'X', 1));
+      lineData.setCell(3, createCellData(DEFAULT_ATTR, 'b', 1));
+      lineData.setCell(4, createCellData(DEFAULT_ATTR, 'b', 1));
       const spans = rowFactory.createRow(lineData, 0, true, undefined, undefined, 2, false, true, 5, widthCache, -1, -1);
       assert.equal(extractHtml(spans),
         '<span>aa</span><span class="xterm-cursor xterm-cursor-block">X</span><span>bb</span>'
@@ -453,7 +453,7 @@ describe('DomRendererRowFactory', () => {
       assert.equal(extractHtml(spans),
         '<span class="xterm-bg-1">    </span>'
       );
-      lineData.setCell(4, CellData.fromCharData([DEFAULT_ATTR, 'a', 1, 'a'.charCodeAt(0)]));
+      lineData.setCell(4, createCellData(DEFAULT_ATTR, 'a', 1));
       spans = rowFactory.createRow(lineData, 0, false, undefined, undefined, 0, false, true, 5, widthCache, -1, -1);
       assert.equal(extractHtml(spans),
         '<span class="xterm-bg-1">    </span><span>a</span>'
@@ -462,9 +462,9 @@ describe('DomRendererRowFactory', () => {
 
     it('should apply correct positive or negative spacing', () => {
       widthCache.setWidths({ '€': 2, '語': 10, '𝄞': 7 });  // €: too small (+3px), 語: exact, 𝄞: too wide (-2px)
-      lineData.setCell(0, CellData.fromCharData([DEFAULT_ATTR, 'a', 1, 'a'.charCodeAt(0)]));
-      lineData.setCell(1, CellData.fromCharData([DEFAULT_ATTR, '€', 1, '€'.charCodeAt(0)]));
-      lineData.setCell(2, CellData.fromCharData([DEFAULT_ATTR, 'c', 1, 'c'.charCodeAt(0)]));
+      lineData.setCell(0, createCellData(DEFAULT_ATTR, 'a', 1));
+      lineData.setCell(1, createCellData(DEFAULT_ATTR, '€', 1));
+      lineData.setCell(2, createCellData(DEFAULT_ATTR, 'c', 1));
       lineData.setCell(3, CellData.fromCharData([DEFAULT_ATTR, '語', 2, 'c'.charCodeAt(0)]));
       lineData.setCell(4, CellData.fromCharData([DEFAULT_ATTR, '𝄞', 1, 'c'.charCodeAt(0)]));
       const spans = rowFactory.createRow(lineData, 0, false, undefined, undefined, 0, false, true, 5, widthCache, -1, -1);
@@ -474,13 +474,13 @@ describe('DomRendererRowFactory', () => {
     });
 
     it('should not merge across link borders', () => {
-      lineData.setCell(0, CellData.fromCharData([DEFAULT_ATTR, 'a', 1, 'a'.charCodeAt(0)]));
-      lineData.setCell(1, CellData.fromCharData([DEFAULT_ATTR, 'a', 1, 'a'.charCodeAt(0)]));
-      lineData.setCell(2, CellData.fromCharData([DEFAULT_ATTR, 'x', 1, 'x'.charCodeAt(0)]));
-      lineData.setCell(3, CellData.fromCharData([DEFAULT_ATTR, 'x', 1, 'x'.charCodeAt(0)]));
-      lineData.setCell(4, CellData.fromCharData([DEFAULT_ATTR, 'x', 1, 'x'.charCodeAt(0)]));
-      lineData.setCell(5, CellData.fromCharData([DEFAULT_ATTR, 'b', 1, 'b'.charCodeAt(0)]));
-      lineData.setCell(6, CellData.fromCharData([DEFAULT_ATTR, 'b', 1, 'b'.charCodeAt(0)]));
+      lineData.setCell(0, createCellData(DEFAULT_ATTR, 'a', 1));
+      lineData.setCell(1, createCellData(DEFAULT_ATTR, 'a', 1));
+      lineData.setCell(2, createCellData(DEFAULT_ATTR, 'x', 1));
+      lineData.setCell(3, createCellData(DEFAULT_ATTR, 'x', 1));
+      lineData.setCell(4, createCellData(DEFAULT_ATTR, 'x', 1));
+      lineData.setCell(5, createCellData(DEFAULT_ATTR, 'b', 1));
+      lineData.setCell(6, createCellData(DEFAULT_ATTR, 'b', 1));
       const spans = rowFactory.createRow(lineData, 0, false, undefined, undefined, 0, false, true, 5, widthCache, 2, 4);
       assert.equal(extractHtml(spans),
         '<span>aa</span><span style="text-decoration: underline;">xxx</span><span>bb</span>'
@@ -488,10 +488,10 @@ describe('DomRendererRowFactory', () => {
     });
 
     it('empty cells included in link underline', () => {
-      lineData.setCell(0, CellData.fromCharData([DEFAULT_ATTR, 'a', 1, 'a'.charCodeAt(0)]));
-      lineData.setCell(1, CellData.fromCharData([DEFAULT_ATTR, 'a', 1, 'a'.charCodeAt(0)]));
-      lineData.setCell(2, CellData.fromCharData([DEFAULT_ATTR, 'x', 1, 'x'.charCodeAt(0)]));
-      lineData.setCell(4, CellData.fromCharData([DEFAULT_ATTR, 'x', 1, 'x'.charCodeAt(0)]));
+      lineData.setCell(0, createCellData(DEFAULT_ATTR, 'a', 1));
+      lineData.setCell(1, createCellData(DEFAULT_ATTR, 'a', 1));
+      lineData.setCell(2, createCellData(DEFAULT_ATTR, 'x', 1));
+      lineData.setCell(4, createCellData(DEFAULT_ATTR, 'x', 1));
       const spans = rowFactory.createRow(lineData, 0, false, undefined, undefined, 0, false, true, 5, widthCache, 2, 4);
       assert.equal(extractHtml(spans),
         '<span>aa</span><span style="text-decoration: underline;">x x</span>'
@@ -500,7 +500,7 @@ describe('DomRendererRowFactory', () => {
 
     it('link range gets capped to actual line borders', () => {
       for (let i = 0; i < 10; ++i) {
-        lineData.setCell(i, CellData.fromCharData([DEFAULT_ATTR, 'a', 1, 'a'.charCodeAt(0)]));
+        lineData.setCell(i, createCellData(DEFAULT_ATTR, 'a', 1));
       }
       const spans = rowFactory.createRow(lineData, 0, false, undefined, undefined, 0, false, true, 5, widthCache, -100, 100);
       assert.equal(extractHtml(spans),
@@ -519,7 +519,7 @@ describe('DomRendererRowFactory', () => {
   function createEmptyLineData(cols: number): IBufferLine {
     const lineData = new BufferLine(cols);
     for (let i = 0; i < cols; i++) {
-      lineData.setCell(i, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]));
+      lineData.setCell(i, NULL_CELL_DATA);
     }
     return lineData;
   }
diff --git a/src/browser/services/CharacterJoinerService.test.ts b/src/browser/services/CharacterJoinerService.test.ts
index 6b5326d93..a0ccc67d6 100644
--- a/src/browser/services/CharacterJoinerService.test.ts
+++ b/src/browser/services/CharacterJoinerService.test.ts
@@ -9,7 +9,7 @@ import { CharacterJoinerService } from 'browser/services/CharacterJoinerService'
 import { BufferLine } from 'common/buffer/BufferLine';
 import { IBufferLine } from 'common/Types';
 import { CellData } from 'common/buffer/CellData';
-import { MockBufferService } from 'common/TestUtils.test';
+import { MockBufferService, createCellData } from 'common/TestUtils.test';
 
 describe('CharacterJoinerService', () => {
   let service: ICharacterJoinerService;
@@ -25,17 +25,17 @@ describe('CharacterJoinerService', () => {
     lines.set(4, new BufferLine(0));
     lines.set(5, lineData([['a', 0x11111111], [' -> b -> c -> '], ['d', 0x22222222]]));
     const line6 = lineData([['wi']]);
-    line6.resize(line6.length + 1, CellData.fromCharData([0, '￥', 2, '￥'.charCodeAt(0)]));
-    line6.resize(line6.length + 1, CellData.fromCharData([0, '', 0, 0]));
+    line6.resize(line6.length + 1, createCellData(0, '￥', 2));
+    line6.resize(line6.length + 1, createCellData(0, '', 0));
     let sub = lineData([['deemo']]);
     let oldSize = line6.length;
-    line6.resize(oldSize + sub.length, CellData.fromCharData([0, '', 0, 0]));
+    line6.resize(oldSize + sub.length, createCellData(0, '', 0));
     for (let i = 0; i < sub.length; ++i) line6.setCell(i + oldSize, sub.loadCell(i, new CellData()));
     line6.resize(line6.length + 1, CellData.fromCharData([0, '\xf0\x9f\x98\x81', 1, 128513]));
-    line6.resize(line6.length + 1, CellData.fromCharData([0, ' ', 1, ' '.charCodeAt(0)]));
+    line6.resize(line6.length + 1, createCellData(0, ' ', 1));
     sub = lineData([['jiabc']]);
     oldSize = line6.length;
-    line6.resize(oldSize + sub.length, CellData.fromCharData([0, '', 0, 0]));
+    line6.resize(oldSize + sub.length, createCellData(0, '', 0));
     for (let i = 0; i < sub.length; ++i) line6.setCell(i + oldSize, sub.loadCell(i, new CellData()));
     lines.set(6, line6);
 
@@ -272,8 +272,8 @@ function lineData(data: IPartialLineData[]): IBufferLine {
     const line = data[i][0];
     const attr = (data[i][1] || 0) as number;
     const offset = tline.length;
-    tline.resize(tline.length + line.split('').length, CellData.fromCharData([0, '', 0, 0]));
-    line.split('').map((char, idx) => tline.setCell(idx + offset, CellData.fromCharData([attr, char, 1, char.charCodeAt(0)])));
+    tline.resize(tline.length + line.split('').length, createCellData(0, '', 0));
+    line.split('').map((char, idx) => tline.setCell(idx + offset, createCellData(attr, char, 1)));
   }
   return tline;
 }
diff --git a/src/browser/services/SelectionService.test.ts b/src/browser/services/SelectionService.test.ts
index 67158def0..8deedb751 100644
--- a/src/browser/services/SelectionService.test.ts
+++ b/src/browser/services/SelectionService.test.ts
@@ -7,7 +7,7 @@ import { assert } from 'chai';
 import { SelectionService, SelectionMode } from './SelectionService';
 import { SelectionModel } from 'browser/selection/SelectionModel';
 import { IBufferLine } from 'common/Types';
-import { MockBufferService, MockOptionsService, MockCoreService } from 'common/TestUtils.test';
+import { MockBufferService, MockOptionsService, MockCoreService, createCellData } from 'common/TestUtils.test';
 import { BufferLine } from 'common/buffer/BufferLine';
 import { IBufferService, IOptionsService } from 'common/services/Services';
 import { MockCoreBrowserService, MockMouseService, MockRenderService } from 'browser/TestUtils.test';
@@ -57,14 +57,14 @@ describe('SelectionService', () => {
   function stringToRow(text: string): IBufferLine {
     const result = new BufferLine(text.length);
     for (let i = 0; i < text.length; i++) {
-      result.setCell(i, CellData.fromCharData([0, text.charAt(i), 1, text.charCodeAt(i)]));
+      result.setCell(i, createCellData(0, text.charAt(i), 1));
     }
     return result;
   }
 
   function stringArrayToRow(chars: string[]): IBufferLine {
     const line = new BufferLine(chars.length);
-    chars.map((c, idx) => line.setCell(idx, CellData.fromCharData([0, c, 1, c.charCodeAt(0)])));
+    chars.map((c, idx) => line.setCell(idx, createCellData(0, c, 1)));
     return line;
   }
 
diff --git a/src/common/TestUtils.test.ts b/src/common/TestUtils.test.ts
index 6e6f0b642..0f982b302 100644
--- a/src/common/TestUtils.test.ts
+++ b/src/common/TestUtils.test.ts
@@ -13,6 +13,14 @@ import { IDecPrivateModes, ICoreMouseEvent, CoreMouseEventType, ICharset, IModes
 import { UnicodeV6 } from 'common/input/UnicodeV6';
 import { IDecorationOptions, IDecoration } from '@xterm/xterm';
 import { Emitter, type IEvent } from 'common/Event';
+import { CellData } from 'common/buffer/CellData';
+import { DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH } from 'common/buffer/Constants';
+
+export function createCellData(attr: number, char: string, width: number): CellData {
+  return CellData.fromCharData([attr, char, width, char.length === 0 ? 0 : char.charCodeAt(0)]);
+}
+
+export const NULL_CELL_DATA = Object.freeze(createCellData(DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH));
 
 export class MockBufferService implements IBufferService {
   public serviceBrand: any;
diff --git a/src/common/Types.ts b/src/common/Types.ts
index a46f47b2a..7ceda21d2 100644
--- a/src/common/Types.ts
+++ b/src/common/Types.ts
@@ -101,13 +101,13 @@ export interface ICharset {
   [key: string]: string | undefined;
 }
 
-export type CharData = [number, string, number, number];
+export type CharData = [attr: number, char: string, width: number, code: number];
 
 export interface IColor {
   readonly css: string;
   readonly rgba: number; // 32-bit int with rgba in each byte
 }
-export type IColorRGB = [number, number, number];
+export type IColorRGB = [red: number, green: number, blue: number];
 
 export interface IExtendedAttrs {
   ext: number;
diff --git a/src/common/buffer/Buffer.test.ts b/src/common/buffer/Buffer.test.ts
index f9e3e1b14..9c013c5de 100644
--- a/src/common/buffer/Buffer.test.ts
+++ b/src/common/buffer/Buffer.test.ts
@@ -6,7 +6,7 @@
 import { assert } from 'chai';
 import { Buffer } from 'common/buffer/Buffer';
 import { CircularList } from 'common/CircularList';
-import { MockOptionsService, MockBufferService, MockLogService } from 'common/TestUtils.test';
+import { MockOptionsService, MockBufferService, MockLogService, createCellData } from 'common/TestUtils.test';
 import { BufferLine, DEFAULT_ATTR_DATA } from 'common/buffer/BufferLine';
 import { CellData } from 'common/buffer/CellData';
 import { ExtendedAttrs } from 'common/buffer/AttributeData';
@@ -1105,10 +1105,10 @@ describe('Buffer', () => {
   describe ('translateBufferLineToString', () => {
     it('should handle selecting a section of ascii text', () => {
       const line = new BufferLine(4);
-      line.setCell(0, CellData.fromCharData([ 0, 'a', 1, 'a'.charCodeAt(0)]));
-      line.setCell(1, CellData.fromCharData([ 0, 'b', 1, 'b'.charCodeAt(0)]));
-      line.setCell(2, CellData.fromCharData([ 0, 'c', 1, 'c'.charCodeAt(0)]));
-      line.setCell(3, CellData.fromCharData([ 0, 'd', 1, 'd'.charCodeAt(0)]));
+      line.setCell(0, createCellData(0, 'a', 1));
+      line.setCell(1, createCellData(0, 'b', 1));
+      line.setCell(2, createCellData(0, 'c', 1));
+      line.setCell(3, createCellData(0, 'd', 1));
       buffer.lines.set(0, line);
 
       const str = buffer.translateBufferLineToString(0, true, 0, 2);
@@ -1117,9 +1117,9 @@ describe('Buffer', () => {
 
     it('should handle a cut-off double width character by including it', () => {
       const line = new BufferLine(3);
-      line.setCell(0, CellData.fromCharData([ 0, '語', 2, 35486 ]));
-      line.setCell(1, CellData.fromCharData([ 0, '', 0, 0]));
-      line.setCell(2, CellData.fromCharData([ 0, 'a', 1, 'a'.charCodeAt(0)]));
+      line.setCell(0, createCellData(0, '語', 2));
+      line.setCell(1, createCellData(0, '', 0));
+      line.setCell(2, createCellData(0, 'a', 1));
       buffer.lines.set(0, line);
 
       const str1 = buffer.translateBufferLineToString(0, true, 0, 1);
@@ -1128,9 +1128,9 @@ describe('Buffer', () => {
 
     it('should handle a zero width character in the middle of the string by not including it', () => {
       const line = new BufferLine(3);
-      line.setCell(0, CellData.fromCharData([ 0, '語', 2, '語'.charCodeAt(0) ]));
-      line.setCell(1, CellData.fromCharData([ 0, '', 0, 0]));
-      line.setCell(2, CellData.fromCharData([ 0, 'a', 1, 'a'.charCodeAt(0)]));
+      line.setCell(0, createCellData(0, '語', 2));
+      line.setCell(1, createCellData(0, '', 0));
+      line.setCell(2, createCellData(0, 'a', 1));
       buffer.lines.set(0, line);
 
       const str0 = buffer.translateBufferLineToString(0, true, 0, 1);
@@ -1145,8 +1145,8 @@ describe('Buffer', () => {
 
     it('should handle single width emojis', () => {
       const line = new BufferLine(2);
-      line.setCell(0, CellData.fromCharData([ 0, '😁', 1, '😁'.charCodeAt(0) ]));
-      line.setCell(1, CellData.fromCharData([ 0, 'a', 1, 'a'.charCodeAt(0)]));
+      line.setCell(0, createCellData(0, '😁', 1));
+      line.setCell(1, createCellData(0, 'a', 1));
       buffer.lines.set(0, line);
 
       const str1 = buffer.translateBufferLineToString(0, true, 0, 1);
@@ -1158,8 +1158,8 @@ describe('Buffer', () => {
 
     it('should handle double width emojis', () => {
       const line = new BufferLine(2);
-      line.setCell(0, CellData.fromCharData([ 0, '😁', 2, '😁'.charCodeAt(0) ]));
-      line.setCell(1, CellData.fromCharData([ 0, '', 0, 0]));
+      line.setCell(0, createCellData(0, '😁', 2));
+      line.setCell(1, createCellData(0, '', 0));
       buffer.lines.set(0, line);
 
       const str1 = buffer.translateBufferLineToString(0, true, 0, 1);
@@ -1169,9 +1169,9 @@ describe('Buffer', () => {
       assert.equal(str2, '😁');
 
       const line2 = new BufferLine(3);
-      line2.setCell(0, CellData.fromCharData([ 0, '😁', 2, '😁'.charCodeAt(0) ]));
-      line2.setCell(1, CellData.fromCharData([ 0, '', 0, 0]));
-      line2.setCell(2, CellData.fromCharData([ 0, 'a', 1, 'a'.charCodeAt(0)]));
+      line2.setCell(0, createCellData(0, '😁', 2));
+      line2.setCell(1, createCellData(0, '', 0));
+      line2.setCell(2, createCellData(0, 'a', 1));
       buffer.lines.set(0, line2);
 
       const str3 = buffer.translateBufferLineToString(0, true, 0, 3);
diff --git a/src/common/buffer/BufferLine.test.ts b/src/common/buffer/BufferLine.test.ts
index 9d08c2bef..100b730d9 100644
--- a/src/common/buffer/BufferLine.test.ts
+++ b/src/common/buffer/BufferLine.test.ts
@@ -8,6 +8,7 @@ import { CellData } from 'common/buffer/CellData';
 import { CharData, IBufferLine } from '../Types';
 import { assert } from 'chai';
 import { AttributeData } from 'common/buffer/AttributeData';
+import { createCellData, NULL_CELL_DATA } from 'common/TestUtils.test';
 
 
 class TestBufferLine extends BufferLine {
@@ -173,78 +174,78 @@ describe('BufferLine', function(): void {
     assert.equal(line.length, 10);
     assert.deepEqual(line.loadCell(0, new CellData()).getAsCharData(), [0, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]);
     assert.equal(line.isWrapped, true);
-    line = new TestBufferLine(10, CellData.fromCharData([123, 'a', 456, 'a'.charCodeAt(0)]), true);
+    line = new TestBufferLine(10, createCellData(123, 'a', 456), true);
     assert.equal(line.length, 10);
     assert.deepEqual(line.loadCell(0, new CellData()).getAsCharData(), [123, 'a', 456, 'a'.charCodeAt(0)]);
     assert.equal(line.isWrapped, true);
   });
   it('insertCells', function(): void {
     const line = new TestBufferLine(3);
-    line.setCell(0, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]));
-    line.setCell(1, CellData.fromCharData([2, 'b', 0, 'b'.charCodeAt(0)]));
-    line.setCell(2, CellData.fromCharData([3, 'c', 0, 'c'.charCodeAt(0)]));
-    line.insertCells(1, 3, CellData.fromCharData([4, 'd', 0, 'd'.charCodeAt(0)]));
+    line.setCell(0, createCellData(1, 'a', 1));
+    line.setCell(1, createCellData(2, 'b', 1));
+    line.setCell(2, createCellData(3, 'c', 1));
+    line.insertCells(1, 3, createCellData(4, 'd', 1));
     assert.deepEqual(line.toArray(), [
-      [1, 'a', 0, 'a'.charCodeAt(0)],
-      [4, 'd', 0, 'd'.charCodeAt(0)],
-      [4, 'd', 0, 'd'.charCodeAt(0)]
+      [1, 'a', 1, 'a'.charCodeAt(0)],
+      [4, 'd', 1, 'd'.charCodeAt(0)],
+      [4, 'd', 1, 'd'.charCodeAt(0)]
     ]);
   });
   it('deleteCells', function(): void {
     const line = new TestBufferLine(5);
-    line.setCell(0, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]));
-    line.setCell(1, CellData.fromCharData([2, 'b', 0, 'b'.charCodeAt(0)]));
-    line.setCell(2, CellData.fromCharData([3, 'c', 0, 'c'.charCodeAt(0)]));
-    line.setCell(3, CellData.fromCharData([4, 'd', 0, 'd'.charCodeAt(0)]));
-    line.setCell(4, CellData.fromCharData([5, 'e', 0, 'e'.charCodeAt(0)]));
-    line.deleteCells(1, 2, CellData.fromCharData([6, 'f', 0, 'f'.charCodeAt(0)]));
+    line.setCell(0, createCellData(1, 'a', 1));
+    line.setCell(1, createCellData(2, 'b', 1));
+    line.setCell(2, createCellData(3, 'c', 1));
+    line.setCell(3, createCellData(4, 'd', 1));
+    line.setCell(4, createCellData(5, 'e', 1));
+    line.deleteCells(1, 2, createCellData(6, 'f', 1));
     assert.deepEqual(line.toArray(), [
-      [1, 'a', 0, 'a'.charCodeAt(0)],
-      [4, 'd', 0, 'd'.charCodeAt(0)],
-      [5, 'e', 0, 'e'.charCodeAt(0)],
-      [6, 'f', 0, 'f'.charCodeAt(0)],
-      [6, 'f', 0, 'f'.charCodeAt(0)]
+      [1, 'a', 1, 'a'.charCodeAt(0)],
+      [4, 'd', 1, 'd'.charCodeAt(0)],
+      [5, 'e', 1, 'e'.charCodeAt(0)],
+      [6, 'f', 1, 'f'.charCodeAt(0)],
+      [6, 'f', 1, 'f'.charCodeAt(0)]
     ]);
   });
   it('replaceCells', function(): void {
     const line = new TestBufferLine(5);
-    line.setCell(0, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]));
-    line.setCell(1, CellData.fromCharData([2, 'b', 0, 'b'.charCodeAt(0)]));
-    line.setCell(2, CellData.fromCharData([3, 'c', 0, 'c'.charCodeAt(0)]));
-    line.setCell(3, CellData.fromCharData([4, 'd', 0, 'd'.charCodeAt(0)]));
-    line.setCell(4, CellData.fromCharData([5, 'e', 0, 'e'.charCodeAt(0)]));
-    line.replaceCells(2, 4, CellData.fromCharData([6, 'f', 0, 'f'.charCodeAt(0)]));
+    line.setCell(0, createCellData(1, 'a', 1));
+    line.setCell(1, createCellData(2, 'b', 1));
+    line.setCell(2, createCellData(3, 'c', 1));
+    line.setCell(3, createCellData(4, 'd', 1));
+    line.setCell(4, createCellData(5, 'e', 1));
+    line.replaceCells(2, 4, createCellData(6, 'f', 1));
     assert.deepEqual(line.toArray(), [
-      [1, 'a', 0, 'a'.charCodeAt(0)],
-      [2, 'b', 0, 'b'.charCodeAt(0)],
-      [6, 'f', 0, 'f'.charCodeAt(0)],
-      [6, 'f', 0, 'f'.charCodeAt(0)],
-      [5, 'e', 0, 'e'.charCodeAt(0)]
+      [1, 'a', 1, 'a'.charCodeAt(0)],
+      [2, 'b', 1, 'b'.charCodeAt(0)],
+      [6, 'f', 1, 'f'.charCodeAt(0)],
+      [6, 'f', 1, 'f'.charCodeAt(0)],
+      [5, 'e', 1, 'e'.charCodeAt(0)]
     ]);
   });
   it('fill', function(): void {
     const line = new TestBufferLine(5);
-    line.setCell(0, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]));
-    line.setCell(1, CellData.fromCharData([2, 'b', 0, 'b'.charCodeAt(0)]));
-    line.setCell(2, CellData.fromCharData([3, 'c', 0, 'c'.charCodeAt(0)]));
-    line.setCell(3, CellData.fromCharData([4, 'd', 0, 'd'.charCodeAt(0)]));
-    line.setCell(4, CellData.fromCharData([5, 'e', 0, 'e'.charCodeAt(0)]));
-    line.fill(CellData.fromCharData([123, 'z', 0, 'z'.charCodeAt(0)]));
+    line.setCell(0, createCellData(1, 'a', 1));
+    line.setCell(1, createCellData(2, 'b', 1));
+    line.setCell(2, createCellData(3, 'c', 1));
+    line.setCell(3, createCellData(4, 'd', 1));
+    line.setCell(4, createCellData(5, 'e', 1));
+    line.fill(createCellData(123, 'z', 1));
     assert.deepEqual(line.toArray(), [
-      [123, 'z', 0, 'z'.charCodeAt(0)],
-      [123, 'z', 0, 'z'.charCodeAt(0)],
-      [123, 'z', 0, 'z'.charCodeAt(0)],
-      [123, 'z', 0, 'z'.charCodeAt(0)],
-      [123, 'z', 0, 'z'.charCodeAt(0)]
+      [123, 'z', 1, 'z'.charCodeAt(0)],
+      [123, 'z', 1, 'z'.charCodeAt(0)],
+      [123, 'z', 1, 'z'.charCodeAt(0)],
+      [123, 'z', 1, 'z'.charCodeAt(0)],
+      [123, 'z', 1, 'z'.charCodeAt(0)]
     ]);
   });
   it('clone', function(): void {
     const line = new TestBufferLine(5, undefined, true);
-    line.setCell(0, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]));
-    line.setCell(1, CellData.fromCharData([2, 'b', 0, 'b'.charCodeAt(0)]));
-    line.setCell(2, CellData.fromCharData([3, 'c', 0, 'c'.charCodeAt(0)]));
-    line.setCell(3, CellData.fromCharData([4, 'd', 0, 'd'.charCodeAt(0)]));
-    line.setCell(4, CellData.fromCharData([5, 'e', 0, 'e'.charCodeAt(0)]));
+    line.setCell(0, createCellData(1, 'a', 1));
+    line.setCell(1, createCellData(2, 'b', 1));
+    line.setCell(2, createCellData(3, 'c', 1));
+    line.setCell(3, createCellData(4, 'd', 1));
+    line.setCell(4, createCellData(5, 'e', 1));
     const line2 = line.clone();
     assert.deepEqual(TestBufferLine.prototype.toArray.apply(line2), line.toArray());
     assert.equal(line2.length, line.length);
@@ -252,12 +253,12 @@ describe('BufferLine', function(): void {
   });
   it('copyFrom', function(): void {
     const line = new TestBufferLine(5);
-    line.setCell(0, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]));
-    line.setCell(1, CellData.fromCharData([2, 'b', 0, 'b'.charCodeAt(0)]));
-    line.setCell(2, CellData.fromCharData([3, 'c', 0, 'c'.charCodeAt(0)]));
-    line.setCell(3, CellData.fromCharData([4, 'd', 0, 'd'.charCodeAt(0)]));
-    line.setCell(4, CellData.fromCharData([5, 'e', 0, 'e'.charCodeAt(0)]));
-    const line2 = new TestBufferLine(5, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]), true);
+    line.setCell(0, createCellData(1, 'a', 1));
+    line.setCell(1, createCellData(2, 'b', 1));
+    line.setCell(2, createCellData(3, 'c', 1));
+    line.setCell(3, createCellData(4, 'd', 1));
+    line.setCell(4, createCellData(5, 'e', 1));
+    const line2 = new TestBufferLine(5, createCellData(1, 'a', 1), true);
     line2.copyFrom(line);
     assert.deepEqual(line2.toArray(), line.toArray());
     assert.equal(line2.length, line.length);
@@ -267,9 +268,9 @@ describe('BufferLine', function(): void {
     // CHAR_DATA_CODE_INDEX resembles current behavior in InputHandler.print
     // --> set code to the last charCodeAt value of the string
     // Note: needs to be fixed once the string pointer is in place
-    const line = new TestBufferLine(2, CellData.fromCharData([1, 'e\u0301', 0, '\u0301'.charCodeAt(0)]));
-    assert.deepEqual(line.toArray(), [[1, 'e\u0301', 0, '\u0301'.charCodeAt(0)], [1, 'e\u0301', 0, '\u0301'.charCodeAt(0)]]);
-    const line2 = new TestBufferLine(5, CellData.fromCharData([1, 'a', 0, '\u0301'.charCodeAt(0)]), true);
+    const line = new TestBufferLine(2, createCellData(1, 'e\u0301', 1));
+    assert.deepEqual(line.toArray(), [[1, 'e\u0301', 1, '\u0301'.charCodeAt(0)], [1, 'e\u0301', 1, '\u0301'.charCodeAt(0)]]);
+    const line2 = new TestBufferLine(5, createCellData(1, 'a', 1), true);
     line2.copyFrom(line);
     assert.deepEqual(line2.toArray(), line.toArray());
     const line3 = line.clone();
@@ -277,72 +278,72 @@ describe('BufferLine', function(): void {
   });
   describe('resize', function(): void {
     it('enlarge(false)', function(): void {
-      const line = new TestBufferLine(5, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]), false);
-      line.resize(10, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]));
-      assert.deepEqual(line.toArray(), (Array(10) as any).fill([1, 'a', 0, 'a'.charCodeAt(0)]));
+      const line = new TestBufferLine(5, createCellData(1, 'a', 1), false);
+      line.resize(10, createCellData(1, 'a', 1));
+      assert.deepEqual(line.toArray(), (Array(10) as any).fill([1, 'a', 1, 'a'.charCodeAt(0)]));
     });
     it('enlarge(true)', function(): void {
-      const line = new TestBufferLine(5, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]), false);
-      line.resize(10, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]));
-      assert.deepEqual(line.toArray(), (Array(10) as any).fill([1, 'a', 0, 'a'.charCodeAt(0)]));
+      const line = new TestBufferLine(5, createCellData(1, 'a', 1), false);
+      line.resize(10, createCellData(1, 'a', 1));
+      assert.deepEqual(line.toArray(), (Array(10) as any).fill([1, 'a', 1, 'a'.charCodeAt(0)]));
     });
     it('shrink(true) - should apply new size', function(): void {
-      const line = new TestBufferLine(10, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]), false);
-      line.resize(5, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]));
-      assert.deepEqual(line.toArray(), (Array(5) as any).fill([1, 'a', 0, 'a'.charCodeAt(0)]));
+      const line = new TestBufferLine(10, createCellData(1, 'a', 1), false);
+      line.resize(5, createCellData(1, 'a', 1));
+      assert.deepEqual(line.toArray(), (Array(5) as any).fill([1, 'a', 1, 'a'.charCodeAt(0)]));
     });
     it('shrink to 0 length', function(): void {
-      const line = new TestBufferLine(10, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]), false);
-      line.resize(0, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]));
-      assert.deepEqual(line.toArray(), (Array(0) as any).fill([1, 'a', 0, 'a'.charCodeAt(0)]));
+      const line = new TestBufferLine(10, createCellData(1, 'a', 1), false);
+      line.resize(0, createCellData(1, 'a', 1));
+      assert.deepEqual(line.toArray(), (Array(0) as any).fill([1, 'a', 1, 'a'.charCodeAt(0)]));
     });
     it('should remove combining data on replaced cells after shrinking then enlarging', () => {
-      const line = new TestBufferLine(10, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]), false);
+      const line = new TestBufferLine(10, createCellData(1, 'a', 1), false);
       line.set(2, [ 0, '😁', 1, '😁'.charCodeAt(0) ]);
       line.set(9, [ 0, '😁', 1, '😁'.charCodeAt(0) ]);
       assert.equal(line.translateToString(), 'aa😁aaaaaa😁');
       assert.equal(Object.keys(line.combined).length, 2);
-      line.resize(5, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]));
+      line.resize(5, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), 'aa😁aa');
-      line.resize(10, CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]));
+      line.resize(10, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), 'aa😁aaaaaaa');
       assert.equal(Object.keys(line.combined).length, 1);
     });
   });
   describe('getTrimLength', function(): void {
     it('empty line', function(): void {
-      const line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]), false);
+      const line = new TestBufferLine(10, NULL_CELL_DATA, false);
       assert.equal(line.getTrimmedLength(), 0);
     });
     it('ASCII', function(): void {
-      const line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]), false);
-      line.setCell(0, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
-      line.setCell(2, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      const line = new TestBufferLine(10, NULL_CELL_DATA, false);
+      line.setCell(0, createCellData(1, 'a', 1));
+      line.setCell(2, createCellData(1, 'a', 1));
       assert.equal(line.getTrimmedLength(), 3);
     });
     it('surrogate', function(): void {
-      const line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]), false);
-      line.setCell(0, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
-      line.setCell(2, CellData.fromCharData([1, '𝄞', 1, '𝄞'.charCodeAt(0)]));
+      const line = new TestBufferLine(10, NULL_CELL_DATA, false);
+      line.setCell(0, createCellData(1, 'a', 1));
+      line.setCell(2, createCellData(1, '𝄞', 1));
       assert.equal(line.getTrimmedLength(), 3);
     });
     it('combining', function(): void {
-      const line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]), false);
-      line.setCell(0, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
-      line.setCell(2, CellData.fromCharData([1, 'e\u0301', 1, '\u0301'.charCodeAt(0)]));
+      const line = new TestBufferLine(10, NULL_CELL_DATA, false);
+      line.setCell(0, createCellData(1, 'a', 1));
+      line.setCell(2, createCellData(1, 'e\u0301', 1));
       assert.equal(line.getTrimmedLength(), 3);
     });
     it('fullwidth', function(): void {
-      const line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]), false);
-      line.setCell(0, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
-      line.setCell(2, CellData.fromCharData([1, '１', 2, '１'.charCodeAt(0)]));
-      line.setCell(3, CellData.fromCharData([0, '', 0, 0]));
+      const line = new TestBufferLine(10, NULL_CELL_DATA, false);
+      line.setCell(0, createCellData(1, 'a', 1));
+      line.setCell(2, createCellData(1, '１', 2));
+      line.setCell(3, createCellData(0, '', 0));
       assert.equal(line.getTrimmedLength(), 4); // also counts null cell after fullwidth
     });
   });
   describe('translateToString with and w\'o trimming', function(): void {
     it('empty line', function(): void {
-      const line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]), false);
+      const line = new TestBufferLine(10, NULL_CELL_DATA, false);
       const columns: number[] = [];
       assert.equal(line.translateToString(false, undefined, undefined, columns), '          ');
       assert.deepEqual(columns, [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
@@ -351,11 +352,11 @@ describe('BufferLine', function(): void {
     });
     it('ASCII', function(): void {
       const columns: number[] = [];
-      const line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]), false);
-      line.setCell(0, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
-      line.setCell(2, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
-      line.setCell(4, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
-      line.setCell(5, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      const line = new TestBufferLine(10, NULL_CELL_DATA, false);
+      line.setCell(0, createCellData(1, 'a', 1));
+      line.setCell(2, createCellData(1, 'a', 1));
+      line.setCell(4, createCellData(1, 'a', 1));
+      line.setCell(5, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(false, undefined, undefined, columns), 'a a aa    ');
       assert.deepEqual(columns, [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
       assert.equal(line.translateToString(true, undefined, undefined, columns), 'a a aa');
@@ -372,11 +373,11 @@ describe('BufferLine', function(): void {
     });
     it('surrogate', function(): void {
       const columns: number[] = [];
-      const line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]), false);
-      line.setCell(0, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
-      line.setCell(2, CellData.fromCharData([1, '𝄞', 1, '𝄞'.charCodeAt(0)]));
-      line.setCell(4, CellData.fromCharData([1, '𝄞', 1, '𝄞'.charCodeAt(0)]));
-      line.setCell(5, CellData.fromCharData([1, '𝄞', 1, '𝄞'.charCodeAt(0)]));
+      const line = new TestBufferLine(10, NULL_CELL_DATA, false);
+      line.setCell(0, createCellData(1, 'a', 1));
+      line.setCell(2, createCellData(1, '𝄞', 1));
+      line.setCell(4, createCellData(1, '𝄞', 1));
+      line.setCell(5, createCellData(1, '𝄞', 1));
       assert.equal(line.translateToString(false, undefined, undefined, columns), 'a 𝄞 𝄞𝄞    ');
       assert.deepEqual(columns, [0, 1, 2, 2, 3, 4, 4, 5, 5, 6, 7, 8, 9, 10]);
       assert.equal(line.translateToString(true, undefined, undefined, columns), 'a 𝄞 𝄞𝄞');
@@ -392,11 +393,11 @@ describe('BufferLine', function(): void {
     });
     it('combining', function(): void {
       const columns: number[] = [];
-      const line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]), false);
-      line.setCell(0, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
-      line.setCell(2, CellData.fromCharData([1, 'e\u0301', 1, '\u0301'.charCodeAt(0)]));
-      line.setCell(4, CellData.fromCharData([1, 'e\u0301', 1, '\u0301'.charCodeAt(0)]));
-      line.setCell(5, CellData.fromCharData([1, 'e\u0301', 1, '\u0301'.charCodeAt(0)]));
+      const line = new TestBufferLine(10, NULL_CELL_DATA, false);
+      line.setCell(0, createCellData(1, 'a', 1));
+      line.setCell(2, createCellData(1, 'e\u0301', 1));
+      line.setCell(4, createCellData(1, 'e\u0301', 1));
+      line.setCell(5, createCellData(1, 'e\u0301', 1));
       assert.equal(line.translateToString(false, undefined, undefined, columns), 'a e\u0301 e\u0301e\u0301    ');
       assert.deepEqual(columns, [0, 1, 2, 2, 3, 4, 4, 5, 5, 6, 7, 8, 9, 10]);
       assert.equal(line.translateToString(true, undefined, undefined, columns), 'a e\u0301 e\u0301e\u0301');
@@ -412,14 +413,14 @@ describe('BufferLine', function(): void {
     });
     it('fullwidth', function(): void {
       const columns: number[] = [];
-      const line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]), false);
-      line.setCell(0, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
-      line.setCell(2, CellData.fromCharData([1, '１', 2, '１'.charCodeAt(0)]));
-      line.setCell(3, CellData.fromCharData([0, '', 0, 0]));
-      line.setCell(5, CellData.fromCharData([1, '１', 2, '１'.charCodeAt(0)]));
-      line.setCell(6, CellData.fromCharData([0, '', 0, 0]));
-      line.setCell(7, CellData.fromCharData([1, '１', 2, '１'.charCodeAt(0)]));
-      line.setCell(8, CellData.fromCharData([0, '', 0, 0]));
+      const line = new TestBufferLine(10, NULL_CELL_DATA, false);
+      line.setCell(0, createCellData(1, 'a', 1));
+      line.setCell(2, createCellData(1, '１', 2));
+      line.setCell(3, createCellData(0, '', 0));
+      line.setCell(5, createCellData(1, '１', 2));
+      line.setCell(6, createCellData(0, '', 0));
+      line.setCell(7, createCellData(1, '１', 2));
+      line.setCell(8, createCellData(0, '', 0));
       assert.equal(line.translateToString(false, undefined, undefined, columns), 'a １ １１ ');
       assert.deepEqual(columns, [0, 1, 2, 4, 5, 7, 9, 10]);
       assert.equal(line.translateToString(true, undefined, undefined, columns), 'a １ １１');
@@ -441,12 +442,12 @@ describe('BufferLine', function(): void {
     });
     it('space at end', function(): void {
       const columns: number[] = [];
-      const line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]), false);
-      line.setCell(0, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
-      line.setCell(2, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
-      line.setCell(4, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
-      line.setCell(5, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
-      line.setCell(6, CellData.fromCharData([1, ' ', 1, ' '.charCodeAt(0)]));
+      const line = new TestBufferLine(10, NULL_CELL_DATA, false);
+      line.setCell(0, createCellData(1, 'a', 1));
+      line.setCell(2, createCellData(1, 'a', 1));
+      line.setCell(4, createCellData(1, 'a', 1));
+      line.setCell(5, createCellData(1, 'a', 1));
+      line.setCell(6, createCellData(1, ' ', 1));
       assert.equal(line.translateToString(false, undefined, undefined, columns), 'a a aa    ');
       assert.deepEqual(columns, [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
       assert.equal(line.translateToString(true, undefined, undefined, columns), 'a a aa ');
@@ -457,7 +458,7 @@ describe('BufferLine', function(): void {
       // sanity check - broken line with invalid out of bound null width cells
       // this can atm happen with deleting/inserting chars in inputhandler by "breaking"
       // fullwidth pairs --> needs to be fixed after settling BufferLine impl
-      const line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
+      const line = new TestBufferLine(10, NULL_CELL_DATA, false);
       assert.equal(line.translateToString(false, undefined, undefined, columns), '          ');
       assert.deepEqual(columns, [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
       assert.equal(line.translateToString(true, undefined, undefined, columns), '');
@@ -465,15 +466,15 @@ describe('BufferLine', function(): void {
     });
     it('should work with endCol=0', () => {
       const columns: number[] = [];
-      const line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
-      line.setCell(0, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      const line = new TestBufferLine(10, NULL_CELL_DATA, false);
+      line.setCell(0, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(true, 0, 0, columns), '');
       assert.deepEqual(columns, [0]);
     });
   });
   describe('addCharToCell', () => {
     it('should set width to 1 for empty cell', () => {
-      const line = new TestBufferLine(3, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]), false);
+      const line = new TestBufferLine(3, NULL_CELL_DATA, false);
       line.addCodepointToCell(0, '\u0301'.charCodeAt(0), 0);
       const cell = line.loadCell(0, new CellData());
       // chars contains single combining char
@@ -483,7 +484,7 @@ describe('BufferLine', function(): void {
       assert.equal(cell.isCombined(), 0);
     });
     it('should add char to combining string in cell', () => {
-      const line = new TestBufferLine(3, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]), false);
+      const line = new TestBufferLine(3, NULL_CELL_DATA, false);
       const cell = line .loadCell(0, new CellData());
       cell.setFromCharData([123, 'e\u0301', 1, 'e\u0301'.charCodeAt(1)]);
       line.setCell(0, cell);
@@ -496,7 +497,7 @@ describe('BufferLine', function(): void {
       assert.equal(cell.isCombined(), Content.IS_COMBINED_MASK);
     });
     it('should create combining string on taken cell', () => {
-      const line = new TestBufferLine(3, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE]), false);
+      const line = new TestBufferLine(3, NULL_CELL_DATA, false);
       const cell = line .loadCell(0, new CellData());
       cell.setFromCharData([123, 'e', 1, 'e'.charCodeAt(1)]);
       line.setCell(0, cell);
@@ -511,98 +512,98 @@ describe('BufferLine', function(): void {
   });
   describe('correct fullwidth handling', () => {
     function populate(line: BufferLine): void {
-      const cell = CellData.fromCharData([1, '￥', 2, '￥'.charCodeAt(0)]);
+      const cell = createCellData(1, '￥', 2);
       for (let i = 0; i < line.length; i += 2) {
         line.setCell(i, cell);
       }
     }
     it('insert - wide char at pos', () => {
-      const line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
+      const line = new TestBufferLine(10, NULL_CELL_DATA, false);
       populate(line);
-      line.insertCells(9, 1, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.insertCells(9, 1, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), '￥￥￥￥ a');
-      line.insertCells(8, 1, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.insertCells(8, 1, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), '￥￥￥￥a ');
-      line.insertCells(1, 1, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.insertCells(1, 1, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), ' a ￥￥￥a');
     });
     it('insert - wide char at end', () => {
-      const line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
+      const line = new TestBufferLine(10, NULL_CELL_DATA, false);
       populate(line);
-      line.insertCells(0, 3, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.insertCells(0, 3, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), 'aaa￥￥￥ ');
-      line.insertCells(4, 1, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.insertCells(4, 1, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), 'aaa a ￥￥');
-      line.insertCells(4, 1, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.insertCells(4, 1, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), 'aaa aa ￥ ');
     });
     it('delete', () => {
-      const line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
+      const line = new TestBufferLine(10, NULL_CELL_DATA, false);
       populate(line);
-      line.deleteCells(0, 1, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.deleteCells(0, 1, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), ' ￥￥￥￥a');
-      line.deleteCells(5, 2, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.deleteCells(5, 2, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), ' ￥￥￥aaa');
-      line.deleteCells(0, 2, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.deleteCells(0, 2, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), ' ￥￥aaaaa');
     });
     it('replace - start at 0', () => {
-      let line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
+      let line = new TestBufferLine(10, NULL_CELL_DATA, false);
       populate(line);
-      line.replaceCells(0, 1, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.replaceCells(0, 1, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), 'a ￥￥￥￥');
-      line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
+      line = new TestBufferLine(10, NULL_CELL_DATA, false);
       populate(line);
-      line.replaceCells(0, 2, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.replaceCells(0, 2, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), 'aa￥￥￥￥');
-      line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
+      line = new TestBufferLine(10, NULL_CELL_DATA, false);
       populate(line);
-      line.replaceCells(0, 3, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.replaceCells(0, 3, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), 'aaa ￥￥￥');
-      line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
+      line = new TestBufferLine(10, NULL_CELL_DATA, false);
       populate(line);
-      line.replaceCells(0, 8, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.replaceCells(0, 8, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), 'aaaaaaaa￥');
-      line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
+      line = new TestBufferLine(10, NULL_CELL_DATA, false);
       populate(line);
-      line.replaceCells(0, 9, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.replaceCells(0, 9, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), 'aaaaaaaaa ');
-      line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
+      line = new TestBufferLine(10, NULL_CELL_DATA, false);
       populate(line);
-      line.replaceCells(0, 10, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.replaceCells(0, 10, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), 'aaaaaaaaaa');
     });
     it('replace - start at 1', () => {
-      let line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
+      let line = new TestBufferLine(10, NULL_CELL_DATA, false);
       populate(line);
-      line.replaceCells(1, 2, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.replaceCells(1, 2, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), ' a￥￥￥￥');
-      line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
+      line = new TestBufferLine(10, NULL_CELL_DATA, false);
       populate(line);
-      line.replaceCells(1, 3, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.replaceCells(1, 3, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), ' aa ￥￥￥');
-      line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
+      line = new TestBufferLine(10, NULL_CELL_DATA, false);
       populate(line);
-      line.replaceCells(1, 4, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.replaceCells(1, 4, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), ' aaa￥￥￥');
-      line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
+      line = new TestBufferLine(10, NULL_CELL_DATA, false);
       populate(line);
-      line.replaceCells(1, 8, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.replaceCells(1, 8, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), ' aaaaaaa￥');
-      line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
+      line = new TestBufferLine(10, NULL_CELL_DATA, false);
       populate(line);
-      line.replaceCells(1, 9, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.replaceCells(1, 9, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), ' aaaaaaaa ');
-      line = new TestBufferLine(10, CellData.fromCharData([DEFAULT_ATTR, NULL_CELL_CHAR, 0, NULL_CELL_CODE]), false);
+      line = new TestBufferLine(10, NULL_CELL_DATA, false);
       populate(line);
-      line.replaceCells(1, 10, CellData.fromCharData([1, 'a', 1, 'a'.charCodeAt(0)]));
+      line.replaceCells(1, 10, createCellData(1, 'a', 1));
       assert.equal(line.translateToString(), ' aaaaaaaaa');
     });
   });
   describe('extended attributes', () => {
     it('setCells', function(): void {
       const line = new TestBufferLine(5);
-      const cell = CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]);
+      const cell = createCellData(1, 'a', 1);
       // no eAttrs
       line.setCell(0, cell);
 
@@ -612,7 +613,7 @@ describe('BufferLine', function(): void {
       line.setCell(1, cell);
 
       // same eAttr, different codepoint
-      cell.content = 65;  // 'A'
+      cell.content = createCellData(1, 'A', 1).content;
       line.setCell(2, cell);
 
       // different eAttr
@@ -625,11 +626,11 @@ describe('BufferLine', function(): void {
       line.setCell(4, cell);
 
       assert.deepEqual(line.toArray(), [
-        [1, 'a', 0, 'a'.charCodeAt(0)],
-        [1, 'a', 0, 'a'.charCodeAt(0)],
-        [1, 'A', 0, 'A'.charCodeAt(0)],
-        [1, 'A', 0, 'A'.charCodeAt(0)],
-        [1, 'A', 0, 'A'.charCodeAt(0)]
+        [1, 'a', 1, 'a'.charCodeAt(0)],
+        [1, 'a', 1, 'a'.charCodeAt(0)],
+        [1, 'A', 1, 'A'.charCodeAt(0)],
+        [1, 'A', 1, 'A'.charCodeAt(0)],
+        [1, 'A', 1, 'A'.charCodeAt(0)]
       ]);
       assert.equal((line as any)._extendedAttrs[0], undefined);
       assert.equal((line as any)._extendedAttrs[1].underlineStyle, UnderlineStyle.CURLY);
@@ -643,7 +644,7 @@ describe('BufferLine', function(): void {
     });
     it('loadCell', () => {
       const line = new TestBufferLine(5);
-      const cell = CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]);
+      const cell = createCellData(1, 'a', 1);
       // no eAttrs
       line.setCell(0, cell);
 
@@ -686,7 +687,7 @@ describe('BufferLine', function(): void {
     });
     it('fill', () => {
       const line = new TestBufferLine(3);
-      const cell = CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]);
+      const cell = createCellData(1, 'a', 1);
       cell.extended.underlineStyle = UnderlineStyle.CURLY;
       cell.bg |= BgFlags.HAS_EXTENDED;
       line.fill(cell);
@@ -696,7 +697,7 @@ describe('BufferLine', function(): void {
     });
     it('insertCells', () => {
       const line = new TestBufferLine(5);
-      const cell = CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]);
+      const cell = createCellData(1, 'a', 1);
       cell.extended.underlineStyle = UnderlineStyle.CURLY;
       cell.bg |= BgFlags.HAS_EXTENDED;
       line.insertCells(1, 3, cell);
@@ -714,7 +715,7 @@ describe('BufferLine', function(): void {
     });
     it('deleteCells', () => {
       const line = new TestBufferLine(5);
-      const fillCell = CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]);
+      const fillCell = createCellData(1, 'a', 1);
       fillCell.extended.underlineStyle = UnderlineStyle.CURLY;
       fillCell.bg |= BgFlags.HAS_EXTENDED;
       line.fill(fillCell);
@@ -729,7 +730,7 @@ describe('BufferLine', function(): void {
     });
     it('replaceCells', () => {
       const line = new TestBufferLine(5);
-      const fillCell = CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]);
+      const fillCell = createCellData(1, 'a', 1);
       fillCell.extended.underlineStyle = UnderlineStyle.CURLY;
       fillCell.bg |= BgFlags.HAS_EXTENDED;
       line.fill(fillCell);
@@ -744,7 +745,7 @@ describe('BufferLine', function(): void {
     });
     it('clone', () => {
       const line = new TestBufferLine(5);
-      const cell = CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]);
+      const cell = createCellData(1, 'a', 1);
       // no eAttrs
       line.setCell(0, cell);
 
@@ -775,7 +776,7 @@ describe('BufferLine', function(): void {
     });
     it('copyFrom', () => {
       const initial = new TestBufferLine(5);
-      const cell = CellData.fromCharData([1, 'a', 0, 'a'.charCodeAt(0)]);
+      const cell = createCellData(1, 'a', 1);
       // no eAttrs
       initial.setCell(0, cell);
 
@@ -798,7 +799,7 @@ describe('BufferLine', function(): void {
       initial.setCell(4, cell);
 
       const line = new TestBufferLine(5);
-      line.fill(CellData.fromCharData([1, 'b', 0, 'b'.charCodeAt(0)]));
+      line.fill(createCellData(1, 'b', 1));
       line.copyFrom(initial);
       assert.equal((line as any)._extendedAttrs[0], (initial as any)._extendedAttrs[0]);
       assert.equal((line as any)._extendedAttrs[1], (initial as any)._extendedAttrs[1]);