fix: factor out getTokenColor lambda

Author: aminya

lib/mixins/canvas-drawer.js

@@ -130,7 +130,10 @@ export default class CanvasDrawer extends Mixin {
     const editor = this.minimap.getTextEditor()
     const editorElement = this.minimap.getTextEditorElement()
 
-    this.updateTokensLayer(firstRow, lastRow, lineHeight, charHeight, charWidth, canvasWidth, this.tokensLayer.context, editor, editorElement, this.displayCodeHighlights, this.ignoreWhitespacesInTokens, this.maxTokensInOneLine)
+    // TODO avoid closure: https://stackoverflow.com/a/46256398/7910299
+    const getTokenColor = this.displayCodeHighlights ? (t) => this.getTokenColor(t, editorElement) : () => this.getDefaultColor(editorElement)
+
+    this.updateTokensLayer(firstRow, lastRow, lineHeight, charHeight, charWidth, canvasWidth, this.tokensLayer.context, editor, getTokenColor, this.ignoreWhitespacesInTokens, this.maxTokensInOneLine)
 
     const decorations = this.minimap.decorationsByTypeThenRows(firstRow, lastRow)
 
@@ -184,13 +187,12 @@ export default class CanvasDrawer extends Mixin {
    * @param {number} canvasWidth  this.tokensLayer.getSize().width
    * @param {CanvasRenderingContext2D} context this.tokensLayer.context
    * @param {TextEditor} editor this.minimap.getTextEditor()
-   * @param {TextEditorElement} editorElement  this.minimap.getTextEditorElement()
-   * @param {boolean} displayCodeHighlights this.displayCodeHighlights
+   * @param {(t: Token) => string} getTokenColor
    * @param {boolean} ignoreWhitespacesInTokens this.ignoreWhitespacesInTokens
    * @param {number} maxTokensInOneLine this.maxTokensInOneLine
    * @access private
    */
-  updateTokensLayer (firstRow, lastRow, lineHeight, charHeight, charWidth, canvasWidth, context, editor, editorElement, displayCodeHighlights, ignoreWhitespacesInTokens, maxTokensInOneLine) {
+  updateTokensLayer (firstRow, lastRow, lineHeight, charHeight, charWidth, canvasWidth, context, editor, getTokenColor, ignoreWhitespacesInTokens, maxTokensInOneLine) {
     const intactRanges = computeIntactRanges(firstRow, lastRow, this.pendingChanges, this.offscreenFirstRow, this.offscreenLastRow)
 
     // NOTE: this method is the hot function of Minimap. Do not refactor. The code is inlined delibarately.
@@ -200,7 +202,7 @@ export default class CanvasDrawer extends Mixin {
     this.tokensLayer.clearCanvas()
 
     if (intactRanges.length === 0) {
-      this.drawLines(firstRow, lastRow, 0, lineHeight, charHeight, charWidth, canvasWidth, context, editor, editorElement, displayCodeHighlights, ignoreWhitespacesInTokens, maxTokensInOneLine)
+      this.drawLines(firstRow, lastRow, 0, lineHeight, charHeight, charWidth, canvasWidth, context, editor, getTokenColor, ignoreWhitespacesInTokens, maxTokensInOneLine)
     } else {
       for (let j = 0, len = intactRanges.length; j < len; j++) {
         const intact = intactRanges[j]
@@ -216,12 +218,12 @@ export default class CanvasDrawer extends Mixin {
       for (let i = 0, len = intactRanges.length; i < len; i++) {
         const range = intactRanges[i]
 
-        this.drawLines(currentRow, range.start, currentRow - firstRow, lineHeight, charHeight, charWidth, canvasWidth, context, editor, editorElement, displayCodeHighlights, ignoreWhitespacesInTokens, maxTokensInOneLine)
+        this.drawLines(currentRow, range.start, currentRow - firstRow, lineHeight, charHeight, charWidth, canvasWidth, context, editor, getTokenColor, ignoreWhitespacesInTokens, maxTokensInOneLine)
 
         currentRow = range.end
       }
       if (currentRow <= lastRow) {
-        this.drawLines(currentRow, lastRow, currentRow - firstRow, lineHeight, charHeight, charWidth, canvasWidth, context, editor, editorElement, displayCodeHighlights, ignoreWhitespacesInTokens, maxTokensInOneLine)
+        this.drawLines(currentRow, lastRow, currentRow - firstRow, lineHeight, charHeight, charWidth, canvasWidth, context, editor, getTokenColor, ignoreWhitespacesInTokens, maxTokensInOneLine)
       }
     }
 
@@ -547,13 +549,12 @@ export default class CanvasDrawer extends Mixin {
    * @param {number} canvasWidth  this.tokensLayer.getSize().width
    * @param {CanvasRenderingContext2D} context this.tokensLayer.context
    * @param {TextEditor} editor this.minimap.getTextEditor()
-   * @param {TextEditorElement} editorElement  this.minimap.getTextEditorElement()
-   * @param {boolean} displayCodeHighlights this.displayCodeHighlights
+   * @param {(t: Token) => string} getTokenColor
    * @param {boolean} ignoreWhitespacesInTokens this.ignoreWhitespacesInTokens
    * @param {number} maxTokensInOneLine this.maxTokensInOneLine
    * @access private
    */
-  drawLines (firstRow, lastRow, offsetRow, lineHeight, charHeight, charWidth, canvasWidth, context, editor, editorElement, displayCodeHighlights, ignoreWhitespacesInTokens, maxTokensInOneLine) {
+  drawLines (firstRow, lastRow, offsetRow, lineHeight, charHeight, charWidth, canvasWidth, context, editor, getTokenColor, ignoreWhitespacesInTokens, maxTokensInOneLine) {
     // NOTE: this method is the hot function of Minimap. Do not refactor. The code is inlined delibarately.
 
     if (firstRow > lastRow) { return }
@@ -572,12 +573,8 @@ export default class CanvasDrawer extends Mixin {
       if (/^\s+$/.test(token.text)) {
         x += token.text.length * charWidth
       } else {
-        const color = displayCodeHighlights
-          ? this.getTokenColor(token, editorElement)
-          : this.getDefaultColor(editorElement)
-
         x = drawToken(
-          context, token.text, color, x, y, charWidth, charHeight, ignoreWhitespacesInTokens
+          context, token.text, getTokenColor(token), x, y, charWidth, charHeight, ignoreWhitespacesInTokens
         )
       }
     })