fix: make drawLines a free function

Author: aminya

lib/mixins/canvas-drawer.js

@@ -23,6 +23,7 @@ export default class CanvasDrawer extends Mixin {
   initializeCanvas () {
     if (SPEC_MODE) {
       // class methods only used for spying the calls
+      this.drawLines = (firstLine, lastLine) => { console.log({ firstLine, lastLine }) }
       this.drawLineDecoration = drawLineDecoration
       this.drawGutterDecoration = drawGutterDecoration
       this.drawHighlightDecoration = drawHighlightDecoration
@@ -197,12 +198,17 @@ export default class CanvasDrawer extends Mixin {
 
     // NOTE: this method is the hot function of Minimap. Do not refactor. The code is inlined delibarately.
 
-    // redrawRangesOnLayer inlined (this.redrawRangesOnLayer(this.tokensLayer, intactRanges, firstRow, lastRow, this.drawLines))
+    // redrawRangesOnLayer inlined (this.redrawRangesOnLayer(this.tokensLayer, intactRanges, firstRow, lastRow, drawLines))
 
     this.tokensLayer.clearCanvas()
 
+    if (SPEC_MODE) {
+      // call the spy
+      this.drawLines(firstRow, lastRow)
+    }
+
     if (intactRanges.length === 0) {
-      this.drawLines(firstRow, lastRow, 0, lineHeight, charHeight, charWidth, canvasWidth, context, editor, getTokenColor, ignoreWhitespacesInTokens, maxTokensInOneLine)
+      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]
@@ -218,12 +224,12 @@ 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, getTokenColor, ignoreWhitespacesInTokens, maxTokensInOneLine)
+        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, getTokenColor, ignoreWhitespacesInTokens, maxTokensInOneLine)
+        drawLines(currentRow, lastRow, currentRow - firstRow, lineHeight, charHeight, charWidth, canvasWidth, context, editor, getTokenColor, ignoreWhitespacesInTokens, maxTokensInOneLine)
       }
     }
 
@@ -439,7 +445,7 @@ export default class CanvasDrawer extends Mixin {
   //         (intact.end - intact.start) * lineHeight
   //       )
   //     }
-  //     this.drawLinesForRanges(method, intactRanges, firstRow, lastRow)
+  //     drawLinesForRanges(method, intactRanges, firstRow, lastRow)
   //   }
   //
   //   layer.resetOffscreenSize()
@@ -533,54 +539,6 @@ export default class CanvasDrawer extends Mixin {
     renderData.context.fill()
   }
 
-  /**
-   * Draws lines on the corresponding layer.
-   *
-   * The lines range to draw is specified by the `firstRow` and `lastRow`
-   * parameters.
-   *
-   * @param  {number} firstRow the first row to render
-   * @param  {number} lastRow the last row to render
-   * @param  {number} offsetRow the relative offset to apply to rows when
-   *                            rendering them
-   * @param {number} lineHeight  this.minimap.getLineHeight() * devicePixelRatio
-   * @param {number} charHeight  this.minimap.getCharHeight() * devicePixelRatio
-   * @param {number} charWidth  this.minimap.getCharWidth() * devicePixelRatio
-   * @param {number} canvasWidth  this.tokensLayer.getSize().width
-   * @param {CanvasRenderingContext2D} context this.tokensLayer.context
-   * @param {TextEditor} editor this.minimap.getTextEditor()
-   * @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, getTokenColor, ignoreWhitespacesInTokens, maxTokensInOneLine) {
-    // NOTE: this method is the hot function of Minimap. Do not refactor. The code is inlined delibarately.
-
-    if (firstRow > lastRow) { return }
-
-    let lastLine, x
-    let y = (offsetRow * lineHeight) - lineHeight
-    eachTokenForScreenRows(firstRow, lastRow, editor, maxTokensInOneLine, (line, token) => {
-      if (lastLine !== line) {
-        x = 0
-        y += lineHeight
-        lastLine = line
-        context.clearRect(x, y, canvasWidth, lineHeight)
-      }
-      if (x > canvasWidth) { return }
-
-      if (/^\s+$/.test(token.text)) {
-        x += token.text.length * charWidth
-      } else {
-        x = drawToken(
-          context, token.text, getTokenColor(token), x, y, charWidth, charHeight, ignoreWhitespacesInTokens
-        )
-      }
-    })
-    context.fill()
-  }
-
   /**
    * Draws the specified decorations for the current `screenRow`.
    *
@@ -718,6 +676,54 @@ function eachTokenForScreenRows (startRow, endRow, editor, maxTokensInOneLine, c
   }
 }
 
+/**
+ * Draws lines on the corresponding layer.
+ *
+ * The lines range to draw is specified by the `firstRow` and `lastRow`
+ * parameters.
+ *
+ * @param  {number} firstRow the first row to render
+ * @param  {number} lastRow the last row to render
+ * @param  {number} offsetRow the relative offset to apply to rows when
+ *                            rendering them
+ * @param {number} lineHeight  this.minimap.getLineHeight() * devicePixelRatio
+ * @param {number} charHeight  this.minimap.getCharHeight() * devicePixelRatio
+ * @param {number} charWidth  this.minimap.getCharWidth() * devicePixelRatio
+ * @param {number} canvasWidth  this.tokensLayer.getSize().width
+ * @param {CanvasRenderingContext2D} context this.tokensLayer.context
+ * @param {TextEditor} editor this.minimap.getTextEditor()
+ * @param {(t: Token) => string} getTokenColor
+ * @param {boolean} ignoreWhitespacesInTokens this.ignoreWhitespacesInTokens
+ * @param {number} maxTokensInOneLine this.maxTokensInOneLine
+ * @access private
+ */
+function 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 }
+
+  let lastLine, x
+  let y = (offsetRow * lineHeight) - lineHeight
+  eachTokenForScreenRows(firstRow, lastRow, editor, maxTokensInOneLine, (line, token) => {
+    if (lastLine !== line) {
+      x = 0
+      y += lineHeight
+      lastLine = line
+      context.clearRect(x, y, canvasWidth, lineHeight)
+    }
+    if (x > canvasWidth) { return }
+
+    if (/^\s+$/.test(token.text)) {
+      x += token.text.length * charWidth
+    } else {
+      x = drawToken(
+        context, token.text, getTokenColor(token), x, y, charWidth, charHeight, ignoreWhitespacesInTokens
+      )
+    }
+  })
+  context.fill()
+}
+
 /**
  * Returns the regexp to replace invisibles substitution characters
  * in editor lines.