Add initial implementation of ReviewCommentTracker

Antonio Scandurra · Antonio Scandurra · commit 7e5c757785e1 · 2016-06-03T14:23:18.000+02:00
diff --git a/package.json b/package.json
@@ -23,6 +23,7 @@
     "etch-stateless": "^1.0.0",
     "keytar": "3.0.2",
     "marked": "^0.3.4",
+    "marker-index": "4.0.0",
     "moment": "2.12.0",
     "nan": "2.x",
     "object-hash": "^1.1.2",
diff --git a/spec/github/review-comment-tracker-spec.js b/spec/github/review-comment-tracker-spec.js
@@ -0,0 +1,153 @@
+'use babel'
+
+import {Point, CompositeDisposable} from 'atom'
+import {diffLines} from 'diff'
+import MarkerIndex from 'marker-index'
+import temp from 'temp'
+
+class ReviewCommentTracker {
+  constructor (editor) {
+    this.editor = editor
+    this.invalidComments = new Map
+    this.subscriptions = new CompositeDisposable()
+
+    // TODO: change to onDidStopChanging
+    this.editor.onDidSave(() => {
+      let invalidComments = this.invalidComments
+      this.invalidComments = new Map
+      invalidComments.forEach(({fileContents, rowInFileContents}, id) => {
+        this.track(id, fileContents, rowInFileContents)
+      })
+    })
+  }
+
+  destroy () {
+    this.subscriptions.dispose()
+  }
+
+  track (id, fileContents, rowInFileContents) {
+    let index = new MarkerIndex()
+    index.insert(id, {row: rowInFileContents, column: 0}, {row: rowInFileContents + 1, column: 0})
+    index.setExclusive(id, true)
+    let currentRow = 0
+    for (let change of diffLines(fileContents, this.editor.getText())) {
+      if (change.added) {
+        let {inside} = index.splice({row: currentRow, column: 0}, {row: 0, column: 0}, {row: change.count, column: 0})
+        if (inside.has(id)) {
+          this.invalidComments.set(id, {fileContents, rowInFileContents})
+          return
+        }
+        // TODO: add specs
+        // currentRow += change.count
+      } else if (change.removed) {
+        let {inside} = index.splice({row: currentRow, column: 0}, {row: change.count, column: 0}, {row: 0, column: 0})
+        if (inside.has(id)) {
+          this.invalidComments.set(id, {fileContents, rowInFileContents})
+          return
+        }
+        // TODO: add specs
+        // currentRow = Math.max(0, currentRow - change.count)
+      } else {
+        currentRow += change.count
+      }
+    }
+
+    let marker = this.editor.markBufferRange(index.getRange(id), {reversed: true, invalidate: 'inside'})
+    let subscription = marker.onDidChange(({isValid}) => {
+      if (!isValid) {
+        this.invalidComments.set(id, {fileContents, rowInFileContents})
+        marker.destroy()
+        subscription.dispose()
+      }
+    })
+    this.editor.decorateMarker(marker, {type: 'block', position: 'after'})
+  }
+}
+
+describe('ReviewCommentTracker', () => {
+  let editor, foo
+
+  beforeEach(() => {
+    editor = atom.workspace.buildTextEditor()
+    foo = new ReviewCommentTracker(editor)
+  })
+
+  it("adds a decoration on the same row when the buffers' contents match", () => {
+    editor.setText('abc\ndef\nghi')
+
+    foo.track(1, 'abc\ndef\nghi', 1)
+
+    let decorations = editor.getDecorations({type: 'block'})
+    expect(decorations.length).toBe(1)
+    expect(decorations[0].getMarker().getHeadBufferPosition()).toEqual([1, 0])
+  })
+
+  it("adds a decoration on a translated row in the current buffer corresponding to row in the original buffer", () => {
+    editor.setText('def\nghi\nABC\nDEF\nlmn\nopq\nrst')
+
+    foo.track(1, 'abc\ndef\nghi\nlmn\nopq\nrst', 3)
+
+    let decorations = editor.getDecorations({type: 'block'})
+    expect(decorations.length).toBe(1)
+    expect(decorations[0].getMarker().getHeadBufferPosition()).toEqual([4, 0])
+
+    editor.setCursorBufferPosition([4, 0])
+    editor.insertNewline()
+
+    decorations = editor.getDecorations({type: 'block'})
+    expect(decorations.length).toBe(1)
+    expect(decorations[0].getMarker().getHeadBufferPosition()).toEqual([5, 0])
+  })
+
+  it("doesn't add a decoration when the comment position doesn't exist anymore, and adds it back on save if it becomes valid again", () => {
+    editor.setText('def\nghi\nABC\nDEF\nGHI\nopq\nrst')
+
+    foo.track(1, 'abc\ndef\nghi\nlmn\nopq\nrst', 3)
+
+    let decorations = editor.getDecorations({type: 'block'})
+    expect(decorations.length).toBe(0)
+
+    editor.setSelectedBufferRange([[4, 0], [4, 3]])
+    editor.insertText('lmn')
+    editor.saveAs(temp.path())
+
+    decorations = editor.getDecorations({type: 'block'})
+    expect(decorations.length).toBe(1)
+    expect(decorations[0].getMarker().getHeadBufferPosition()).toEqual([4, 0])
+  })
+
+  it("removes decorations as soon as they become invalid and adds them back on save if they become valid again", () => {
+    editor.setText('def\nghi\nABC\nDEF\nlmn\nopq\nrst')
+
+    foo.track(1, 'abc\ndef\nghi\nlmn\nopq\nrst', 3)
+    editor.setCursorBufferPosition([4, 0])
+    editor.deleteLine()
+
+    let decorations = editor.getDecorations({type: 'block'})
+    expect(decorations.length).toBe(0)
+
+    editor.undo()
+    editor.saveAs(temp.path())
+
+    decorations = editor.getDecorations({type: 'block'})
+    expect(decorations.length).toBe(1)
+    expect(decorations[0].getMarker().getHeadBufferPosition()).toEqual([4, 0])
+
+    editor.redo()
+
+    decorations = editor.getDecorations({type: 'block'})
+    expect(decorations.length).toBe(0)
+
+    editor.save()
+
+    decorations = editor.getDecorations({type: 'block'})
+    expect(decorations.length).toBe(0)
+
+    editor.undo()
+    editor.save()
+
+    decorations = editor.getDecorations({type: 'block'})
+    expect(decorations.length).toBe(1)
+    expect(decorations[0].getMarker().getHeadBufferPosition()).toEqual([4, 0])
+  })
+})
