diff --git a/packages/e2e/src/diff.coverage-blank-line-deletion.ts b/packages/e2e/src/diff.coverage-blank-line-deletion.ts
new file mode 100644
index 0000000..819cd6f
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-blank-line-deletion.ts
@@ -0,0 +1,16 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-blank-line-deletion'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'one\n\ntwo')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'one\ntwo')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const deletedRows = Locator('.DiffEditorContentLeft .EditorRow.Deletion')
+  await expect(deletedRows).toHaveCount(1)
+  await expect(deletedRows).toHaveText('')
+}
diff --git a/packages/e2e/src/diff.coverage-blank-line-insertion.ts b/packages/e2e/src/diff.coverage-blank-line-insertion.ts
new file mode 100644
index 0000000..da27878
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-blank-line-insertion.ts
@@ -0,0 +1,16 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-blank-line-insertion'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'one\ntwo')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'one\n\ntwo')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const insertedRows = Locator('.DiffEditorContentRight .EditorRow.Insertion')
+  await expect(insertedRows).toHaveCount(1)
+  await expect(insertedRows).toHaveText('')
+}
diff --git a/packages/e2e/src/diff.coverage-cjk-line-replacement.ts b/packages/e2e/src/diff.coverage-cjk-line-replacement.ts
new file mode 100644
index 0000000..c2abcce
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-cjk-line-replacement.ts
@@ -0,0 +1,17 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-cjk-line-replacement'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, '状態: 保留')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, '状態: 完了')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const leftRows = Locator('.DiffEditorContentLeft .DiffEditorRows')
+  const rightRows = Locator('.DiffEditorContentRight .DiffEditorRows')
+  await expect(leftRows).toHaveText('状態: 保留')
+  await expect(rightRows).toHaveText('状態: 完了')
+}
diff --git a/packages/e2e/src/diff.coverage-combining-mark-replacement.ts b/packages/e2e/src/diff.coverage-combining-mark-replacement.ts
new file mode 100644
index 0000000..0ca0c34
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-combining-mark-replacement.ts
@@ -0,0 +1,16 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-combining-mark-replacement'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'Cafe\u{301}')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'Cafe')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const changedTokens = Locator('.DiffToken--changed')
+  await expect(changedTokens).toHaveCount(1)
+  await expect(changedTokens).toHaveText('\u{301}')
+}
diff --git a/packages/e2e/src/diff.coverage-consecutive-lines-deletion.ts b/packages/e2e/src/diff.coverage-consecutive-lines-deletion.ts
new file mode 100644
index 0000000..cee559c
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-consecutive-lines-deletion.ts
@@ -0,0 +1,18 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-consecutive-lines-deletion'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'start\nremoved one\nremoved two\nend')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'start\nend')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const deletedRows = Locator('.DiffEditorContentLeft .EditorRow.Deletion')
+  const secondDeletedRow = deletedRows.nth(1)
+  await expect(deletedRows).toHaveCount(2)
+  await expect(deletedRows.first()).toHaveText('removed one')
+  await expect(secondDeletedRow).toHaveText('removed two')
+}
diff --git a/packages/e2e/src/diff.coverage-consecutive-lines-insertion.ts b/packages/e2e/src/diff.coverage-consecutive-lines-insertion.ts
new file mode 100644
index 0000000..ef68fda
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-consecutive-lines-insertion.ts
@@ -0,0 +1,18 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-consecutive-lines-insertion'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'start\nend')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'start\nadded one\nadded two\nend')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const insertedRows = Locator('.DiffEditorContentRight .EditorRow.Insertion')
+  const secondInsertedRow = insertedRows.nth(1)
+  await expect(insertedRows).toHaveCount(2)
+  await expect(insertedRows.first()).toHaveText('added one')
+  await expect(secondInsertedRow).toHaveText('added two')
+}
diff --git a/packages/e2e/src/diff.coverage-cursor-at-document-end.ts b/packages/e2e/src/diff.coverage-cursor-at-document-end.ts
new file mode 100644
index 0000000..e57ef0b
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-cursor-at-document-end.ts
@@ -0,0 +1,17 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-cursor-at-document-end'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'alpha\nbeta')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'alpha\nbeta')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.setCursorPosition', 4, 1)
+
+  const cursor = Locator('.EditorCursorRight')
+  await expect(cursor).toHaveCSS('left', '85px')
+  await expect(cursor).toHaveCSS('top', '20px')
+}
diff --git a/packages/e2e/src/diff.coverage-cursor-at-document-start.ts b/packages/e2e/src/diff.coverage-cursor-at-document-start.ts
new file mode 100644
index 0000000..d8a45e4
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-cursor-at-document-start.ts
@@ -0,0 +1,17 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-cursor-at-document-start'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'alpha\nbeta')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'alpha\nbeta')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.setCursorPosition', 0, 0)
+
+  const cursor = Locator('.EditorCursorRight')
+  await expect(cursor).toHaveCSS('left', '49px')
+  await expect(cursor).toHaveCSS('top', '0px')
+}
diff --git a/packages/e2e/src/diff.coverage-cursor-down-clamps-column.ts b/packages/e2e/src/diff.coverage-cursor-down-clamps-column.ts
new file mode 100644
index 0000000..1ec7759
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-cursor-down-clamps-column.ts
@@ -0,0 +1,18 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-cursor-down-clamps-column'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'alpha\nb')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'alpha\nb')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.setCursorPosition', 5, 0)
+  await Command.execute('DiffView.moveCursorDown')
+
+  const cursor = Locator('.EditorCursorRight')
+  await expect(cursor).toHaveCSS('left', '58px')
+  await expect(cursor).toHaveCSS('top', '20px')
+}
diff --git a/packages/e2e/src/diff.coverage-cursor-down-last-line.ts b/packages/e2e/src/diff.coverage-cursor-down-last-line.ts
new file mode 100644
index 0000000..7f54ec4
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-cursor-down-last-line.ts
@@ -0,0 +1,18 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-cursor-down-last-line'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'alpha\nbeta')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'alpha\nbeta')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.setCursorPosition', 2, 1)
+  await Command.execute('DiffView.moveCursorDown')
+
+  const cursor = Locator('.EditorCursorRight')
+  await expect(cursor).toHaveCSS('left', '67px')
+  await expect(cursor).toHaveCSS('top', '20px')
+}
diff --git a/packages/e2e/src/diff.coverage-cursor-left-document-start.ts b/packages/e2e/src/diff.coverage-cursor-left-document-start.ts
new file mode 100644
index 0000000..e17cae2
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-cursor-left-document-start.ts
@@ -0,0 +1,18 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-cursor-left-document-start'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'alpha')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'alpha')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.setCursorPosition', 0, 0)
+  await Command.execute('DiffView.moveCursorLeft')
+
+  const cursor = Locator('.EditorCursorRight')
+  await expect(cursor).toHaveCSS('left', '49px')
+  await expect(cursor).toHaveCSS('top', '0px')
+}
diff --git a/packages/e2e/src/diff.coverage-cursor-right-document-end.ts b/packages/e2e/src/diff.coverage-cursor-right-document-end.ts
new file mode 100644
index 0000000..fa4e5d5
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-cursor-right-document-end.ts
@@ -0,0 +1,18 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-cursor-right-document-end'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'alpha')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'alpha')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.setCursorPosition', 5, 0)
+  await Command.execute('DiffView.moveCursorRight')
+
+  const cursor = Locator('.EditorCursorRight')
+  await expect(cursor).toHaveCSS('left', '94px')
+  await expect(cursor).toHaveCSS('top', '0px')
+}
diff --git a/packages/e2e/src/diff.coverage-cursor-up-clamps-column.ts b/packages/e2e/src/diff.coverage-cursor-up-clamps-column.ts
new file mode 100644
index 0000000..d0b0c8a
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-cursor-up-clamps-column.ts
@@ -0,0 +1,18 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-cursor-up-clamps-column'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'a\ngamma')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'a\ngamma')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.setCursorPosition', 5, 1)
+  await Command.execute('DiffView.moveCursorUp')
+
+  const cursor = Locator('.EditorCursorRight')
+  await expect(cursor).toHaveCSS('left', '58px')
+  await expect(cursor).toHaveCSS('top', '0px')
+}
diff --git a/packages/e2e/src/diff.coverage-cursor-up-first-line.ts b/packages/e2e/src/diff.coverage-cursor-up-first-line.ts
new file mode 100644
index 0000000..a439e15
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-cursor-up-first-line.ts
@@ -0,0 +1,18 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-cursor-up-first-line'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'alpha\nbeta')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'alpha\nbeta')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.setCursorPosition', 2, 0)
+  await Command.execute('DiffView.moveCursorUp')
+
+  const cursor = Locator('.EditorCursorRight')
+  await expect(cursor).toHaveCSS('left', '67px')
+  await expect(cursor).toHaveCSS('top', '0px')
+}
diff --git a/packages/e2e/src/diff.coverage-delete-left-character.ts b/packages/e2e/src/diff.coverage-delete-left-character.ts
new file mode 100644
index 0000000..9aaad18
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-delete-left-character.ts
@@ -0,0 +1,17 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-delete-left-character'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'pear')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'pear')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.setCursorPosition', 2, 0)
+  await Command.execute('DiffView.deleteLeft')
+
+  const afterRows = Locator('.DiffEditorContentRight .DiffEditorRows')
+  await expect(afterRows).toHaveText('par')
+}
diff --git a/packages/e2e/src/diff.coverage-delete-left-document-start.ts b/packages/e2e/src/diff.coverage-delete-left-document-start.ts
new file mode 100644
index 0000000..d4373b8
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-delete-left-document-start.ts
@@ -0,0 +1,17 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-delete-left-document-start'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'alpha')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'alpha')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.setCursorPosition', 0, 0)
+  await Command.execute('DiffView.deleteLeft')
+
+  const afterRows = Locator('.DiffEditorContentRight .DiffEditorRows')
+  await expect(afterRows).toHaveText('alpha')
+}
diff --git a/packages/e2e/src/diff.coverage-delete-left-line-break.ts b/packages/e2e/src/diff.coverage-delete-left-line-break.ts
new file mode 100644
index 0000000..b5e3596
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-delete-left-line-break.ts
@@ -0,0 +1,17 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-delete-left-line-break'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'alpha\nbeta')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'alpha\nbeta')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.setCursorPosition', 0, 1)
+  await Command.execute('DiffView.deleteLeft')
+
+  const afterRows = Locator('.DiffEditorContentRight .DiffEditorRows')
+  await expect(afterRows).toHaveText('alphabeta')
+}
diff --git a/packages/e2e/src/diff.coverage-delete-right-document-end.ts b/packages/e2e/src/diff.coverage-delete-right-document-end.ts
new file mode 100644
index 0000000..1a4380f
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-delete-right-document-end.ts
@@ -0,0 +1,17 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-delete-right-document-end'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'alpha\nbeta')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'alpha\nbeta')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.setCursorPosition', 4, 1)
+  await Command.execute('DiffView.deleteRight')
+
+  const afterRows = Locator('.DiffEditorContentRight .DiffEditorRows')
+  await expect(afterRows).toHaveText('alphabeta')
+}
diff --git a/packages/e2e/src/diff.coverage-delete-right-empty-document.ts b/packages/e2e/src/diff.coverage-delete-right-empty-document.ts
new file mode 100644
index 0000000..e789abc
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-delete-right-empty-document.ts
@@ -0,0 +1,17 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-delete-right-empty-document'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, '')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, '')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.setCursorPosition', 0, 0)
+  await Command.execute('DiffView.deleteRight')
+
+  const afterRows = Locator('.DiffEditorContentRight .DiffEditorRows')
+  await expect(afterRows).toHaveText('')
+}
diff --git a/packages/e2e/src/diff.coverage-final-line-deletion.ts b/packages/e2e/src/diff.coverage-final-line-deletion.ts
new file mode 100644
index 0000000..f4bb4bc
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-final-line-deletion.ts
@@ -0,0 +1,16 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-final-line-deletion'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'shared one\nshared two\nold final')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'shared one\nshared two')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const deletedRows = Locator('.DiffEditorContentLeft .EditorRow.Deletion')
+  await expect(deletedRows).toHaveCount(1)
+  await expect(deletedRows).toHaveText('old final')
+}
diff --git a/packages/e2e/src/diff.coverage-final-line-insertion.ts b/packages/e2e/src/diff.coverage-final-line-insertion.ts
new file mode 100644
index 0000000..2b30fdd
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-final-line-insertion.ts
@@ -0,0 +1,16 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-final-line-insertion'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'shared one\nshared two')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'shared one\nshared two\nnew final')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const insertedRows = Locator('.DiffEditorContentRight .EditorRow.Insertion')
+  await expect(insertedRows).toHaveCount(1)
+  await expect(insertedRows).toHaveText('new final')
+}
diff --git a/packages/e2e/src/diff.coverage-final-line-replacement.ts b/packages/e2e/src/diff.coverage-final-line-replacement.ts
new file mode 100644
index 0000000..f5d24a5
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-final-line-replacement.ts
@@ -0,0 +1,17 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-final-line-replacement'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'shared\nbefore final')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'shared\nafter final')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const deletedRows = Locator('.DiffEditorContentLeft .EditorRow.Deletion')
+  const insertedRows = Locator('.DiffEditorContentRight .EditorRow.Insertion')
+  await expect(deletedRows).toHaveText('before final')
+  await expect(insertedRows).toHaveText('after final')
+}
diff --git a/packages/e2e/src/diff.coverage-first-line-deletion.ts b/packages/e2e/src/diff.coverage-first-line-deletion.ts
new file mode 100644
index 0000000..cd70818
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-first-line-deletion.ts
@@ -0,0 +1,16 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-first-line-deletion'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'old first\nshared one\nshared two')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'shared one\nshared two')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const deletedRows = Locator('.DiffEditorContentLeft .EditorRow.Deletion')
+  await expect(deletedRows).toHaveCount(1)
+  await expect(deletedRows).toHaveText('old first')
+}
diff --git a/packages/e2e/src/diff.coverage-first-line-insertion.ts b/packages/e2e/src/diff.coverage-first-line-insertion.ts
new file mode 100644
index 0000000..e994181
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-first-line-insertion.ts
@@ -0,0 +1,16 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-first-line-insertion'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'shared one\nshared two')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'new first\nshared one\nshared two')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const insertedRows = Locator('.DiffEditorContentRight .EditorRow.Insertion')
+  await expect(insertedRows).toHaveCount(1)
+  await expect(insertedRows).toHaveText('new first')
+}
diff --git a/packages/e2e/src/diff.coverage-first-line-replacement.ts b/packages/e2e/src/diff.coverage-first-line-replacement.ts
new file mode 100644
index 0000000..ab5ba40
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-first-line-replacement.ts
@@ -0,0 +1,17 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-first-line-replacement'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'before first\nshared')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'after first\nshared')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const deletedRows = Locator('.DiffEditorContentLeft .EditorRow.Deletion')
+  const insertedRows = Locator('.DiffEditorContentRight .EditorRow.Insertion')
+  await expect(deletedRows).toHaveText('before first')
+  await expect(insertedRows).toHaveText('after first')
+}
diff --git a/packages/e2e/src/diff.coverage-inline-empty-after.ts b/packages/e2e/src/diff.coverage-inline-empty-after.ts
new file mode 100644
index 0000000..0b79adb
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-inline-empty-after.ts
@@ -0,0 +1,16 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-inline-empty-after'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'removed')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, '')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.setDiffMode', 'inline')
+
+  const inlineRows = Locator('.InlineDiffEditor .DiffEditorRows')
+  await expect(inlineRows).toContainText('- removed')
+}
diff --git a/packages/e2e/src/diff.coverage-inline-empty-before.ts b/packages/e2e/src/diff.coverage-inline-empty-before.ts
new file mode 100644
index 0000000..bc966a4
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-inline-empty-before.ts
@@ -0,0 +1,16 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-inline-empty-before'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, '')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'added')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.setDiffMode', 'inline')
+
+  const inlineRows = Locator('.InlineDiffEditor .DiffEditorRows')
+  await expect(inlineRows).toContainText('+ added')
+}
diff --git a/packages/e2e/src/diff.coverage-inline-identical-content.ts b/packages/e2e/src/diff.coverage-inline-identical-content.ts
new file mode 100644
index 0000000..438fed4
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-inline-identical-content.ts
@@ -0,0 +1,19 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-inline-identical-content'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'shared one\nshared two')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'shared one\nshared two')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.setDiffMode', 'inline')
+
+  const inlineRows = Locator('.InlineDiffEditor .DiffEditorRows')
+  const changedRows = Locator('.InlineDiffEditor .EditorRow.Insertion, .InlineDiffEditor .EditorRow.Deletion')
+  await expect(inlineRows).toContainText('shared one')
+  await expect(inlineRows).toContainText('shared two')
+  await expect(changedRows).toHaveCount(0)
+}
diff --git a/packages/e2e/src/diff.coverage-middle-line-deletion.ts b/packages/e2e/src/diff.coverage-middle-line-deletion.ts
new file mode 100644
index 0000000..11d0543
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-middle-line-deletion.ts
@@ -0,0 +1,16 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-middle-line-deletion'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'shared one\nold middle\nshared two')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'shared one\nshared two')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const deletedRows = Locator('.DiffEditorContentLeft .EditorRow.Deletion')
+  await expect(deletedRows).toHaveCount(1)
+  await expect(deletedRows).toHaveText('old middle')
+}
diff --git a/packages/e2e/src/diff.coverage-middle-line-insertion.ts b/packages/e2e/src/diff.coverage-middle-line-insertion.ts
new file mode 100644
index 0000000..38e6822
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-middle-line-insertion.ts
@@ -0,0 +1,16 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-middle-line-insertion'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'shared one\nshared two')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'shared one\nnew middle\nshared two')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const insertedRows = Locator('.DiffEditorContentRight .EditorRow.Insertion')
+  await expect(insertedRows).toHaveCount(1)
+  await expect(insertedRows).toHaveText('new middle')
+}
diff --git a/packages/e2e/src/diff.coverage-middle-line-replacement.ts b/packages/e2e/src/diff.coverage-middle-line-replacement.ts
new file mode 100644
index 0000000..c515013
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-middle-line-replacement.ts
@@ -0,0 +1,17 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-middle-line-replacement'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'shared one\nbefore middle\nshared two')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'shared one\nafter middle\nshared two')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const deletedRows = Locator('.DiffEditorContentLeft .EditorRow.Deletion')
+  const insertedRows = Locator('.DiffEditorContentRight .EditorRow.Insertion')
+  await expect(deletedRows).toHaveText('before middle')
+  await expect(insertedRows).toHaveText('after middle')
+}
diff --git a/packages/e2e/src/diff.coverage-mode-toggle-empty-after-roundtrip.ts b/packages/e2e/src/diff.coverage-mode-toggle-empty-after-roundtrip.ts
new file mode 100644
index 0000000..6b5cad0
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-mode-toggle-empty-after-roundtrip.ts
@@ -0,0 +1,20 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-mode-toggle-empty-after-roundtrip'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'removed')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, '')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.toggleDiffMode')
+
+  const inlineRows = Locator('.InlineDiffEditor .DiffEditorRows')
+  await expect(inlineRows).toContainText('- removed')
+
+  await Command.execute('DiffView.toggleDiffMode')
+  const leftRows = Locator('.DiffEditorContentLeft .DiffEditorRows')
+  await expect(leftRows).toHaveText('removed')
+}
diff --git a/packages/e2e/src/diff.coverage-mode-toggle-empty-before-roundtrip.ts b/packages/e2e/src/diff.coverage-mode-toggle-empty-before-roundtrip.ts
new file mode 100644
index 0000000..0155369
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-mode-toggle-empty-before-roundtrip.ts
@@ -0,0 +1,20 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-mode-toggle-empty-before-roundtrip'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, '')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'added')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+  await Command.execute('DiffView.toggleDiffMode')
+
+  const inlineRows = Locator('.InlineDiffEditor .DiffEditorRows')
+  await expect(inlineRows).toContainText('+ added')
+
+  await Command.execute('DiffView.toggleDiffMode')
+  const rightRows = Locator('.DiffEditorContentRight .DiffEditorRows')
+  await expect(rightRows).toHaveText('added')
+}
diff --git a/packages/e2e/src/diff.coverage-rtl-line-replacement.ts b/packages/e2e/src/diff.coverage-rtl-line-replacement.ts
new file mode 100644
index 0000000..4ef0d24
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-rtl-line-replacement.ts
@@ -0,0 +1,17 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-rtl-line-replacement'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'الحالة: قديم')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'الحالة: جديد')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const leftRows = Locator('.DiffEditorContentLeft .DiffEditorRows')
+  const rightRows = Locator('.DiffEditorContentRight .DiffEditorRows')
+  await expect(leftRows).toHaveText('الحالة: قديم')
+  await expect(rightRows).toHaveText('الحالة: جديد')
+}
diff --git a/packages/e2e/src/diff.coverage-scroll-roundtrip.ts b/packages/e2e/src/diff.coverage-scroll-roundtrip.ts
new file mode 100644
index 0000000..c9ebde9
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-scroll-roundtrip.ts
@@ -0,0 +1,24 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-scroll-roundtrip'
+
+const getContent = (): string => {
+  return Array.from({ length: 80 }, (_, index) => `line ${index + 1}`).join('\n')
+}
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  const content = getContent()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, content)
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, content)
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const rightRows = Locator('.DiffEditorContentRight .DiffEditorRows')
+  await expect(rightRows).toContainText('line 1')
+  await Command.execute('DiffView.handleWheel', 0, 9999)
+  await expect(rightRows).toContainText('line 80')
+  await Command.execute('DiffView.handleWheel', 0, -9999)
+  await expect(rightRows).toContainText('line 1')
+}
diff --git a/packages/e2e/src/diff.coverage-separated-line-deletions.ts b/packages/e2e/src/diff.coverage-separated-line-deletions.ts
new file mode 100644
index 0000000..b984c10
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-separated-line-deletions.ts
@@ -0,0 +1,18 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-separated-line-deletions'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'removed first\none\ntwo\nremoved second\nthree')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'one\ntwo\nthree')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const deletedRows = Locator('.DiffEditorContentLeft .EditorRow.Deletion')
+  const secondDeletedRow = deletedRows.nth(1)
+  await expect(deletedRows).toHaveCount(2)
+  await expect(deletedRows.first()).toHaveText('removed first')
+  await expect(secondDeletedRow).toHaveText('removed second')
+}
diff --git a/packages/e2e/src/diff.coverage-separated-line-insertions.ts b/packages/e2e/src/diff.coverage-separated-line-insertions.ts
new file mode 100644
index 0000000..65f1ba2
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-separated-line-insertions.ts
@@ -0,0 +1,18 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-separated-line-insertions'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'one\ntwo\nthree')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'added first\none\ntwo\nadded second\nthree')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const insertedRows = Locator('.DiffEditorContentRight .EditorRow.Insertion')
+  const secondInsertedRow = insertedRows.nth(1)
+  await expect(insertedRows).toHaveCount(2)
+  await expect(insertedRows.first()).toHaveText('added first')
+  await expect(secondInsertedRow).toHaveText('added second')
+}
diff --git a/packages/e2e/src/diff.coverage-single-line-deletion.ts b/packages/e2e/src/diff.coverage-single-line-deletion.ts
new file mode 100644
index 0000000..30d6d10
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-single-line-deletion.ts
@@ -0,0 +1,16 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-single-line-deletion'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'removed')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, '')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const deletedRows = Locator('.DiffEditorContentLeft .EditorRow.Deletion')
+  await expect(deletedRows).toHaveCount(1)
+  await expect(deletedRows).toHaveText('removed')
+}
diff --git a/packages/e2e/src/diff.coverage-single-line-insertion.ts b/packages/e2e/src/diff.coverage-single-line-insertion.ts
new file mode 100644
index 0000000..dc948ba
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-single-line-insertion.ts
@@ -0,0 +1,16 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-single-line-insertion'
+
+export const test: Test = async ({ DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, '')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'added')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const insertedRows = Locator('.DiffEditorContentRight .EditorRow.Insertion')
+  await expect(insertedRows).toHaveCount(1)
+  await expect(insertedRows).toHaveText('added')
+}
diff --git a/packages/e2e/src/diff.coverage-whitespace-toggle-roundtrip.ts b/packages/e2e/src/diff.coverage-whitespace-toggle-roundtrip.ts
new file mode 100644
index 0000000..ed87fed
--- /dev/null
+++ b/packages/e2e/src/diff.coverage-whitespace-toggle-roundtrip.ts
@@ -0,0 +1,19 @@
+import type { Test } from '@lvce-editor/test-with-playwright'
+
+export const name = 'diff.coverage-whitespace-toggle-roundtrip'
+
+export const test: Test = async ({ Command, DiffView, expect, FileSystem, Locator, Workspace }) => {
+  const tmpDir = await FileSystem.getTmpDir()
+  await FileSystem.writeFile(`${tmpDir}/before.txt`, 'before value')
+  await FileSystem.writeFile(`${tmpDir}/after.txt`, 'after value')
+  await Workspace.setPath(tmpDir)
+
+  await DiffView.open(`${tmpDir}/before.txt`, `${tmpDir}/after.txt`)
+
+  const activeToggle = Locator('.DiffEditorWhitespaceToggleActive')
+  await expect(activeToggle).toHaveCount(0)
+  await Command.execute('DiffView.toggleWhitespace')
+  await expect(activeToggle).toHaveCount(1)
+  await Command.execute('DiffView.toggleWhitespace')
+  await expect(activeToggle).toHaveCount(0)
+}