Rewrite GitGraph.js (#12137)

The current vendored gitgraph.js is no longer maintained and is
difficult to understand, fix and maintain.

This PR completely rewrites its logic - hopefully in a clearer fashion
and easier to maintain.

It also includes @silverwind's improvements of coloring the commit dots
and preventing the flash of incorrect content.

Further changes to contemplate in future will be abstracting out of the
flows to an object, storing the involved commit references on the flows
etc. However, this is probably a required step for this.

Replaces #12131
Fixes #11981 (part 3)

Signed-off-by: Andrew Thornton <art27@cantab.net>

1 files changed, 0 insertions, 432 deletions

diff --git a/web_src/js/vendor/gitgraph.js b/web_src/js/vendor/gitgraph.js
deleted file mode 100644
index 0cf5d0f75b..0000000000
--- a/web_src/js/vendor/gitgraph.js
+++ /dev/null
@@ -1,432 +0,0 @@
-/* This is a customized version of https://github.com/bluef/gitgraph.js/blob/master/gitgraph.js
-   Changes include conversion to ES6 and linting fixes */
-
-/*
- * @license magnet:?xt=urn:btih:c80d50af7d3db9be66a4d0a86db0286e4fd33292&dn=bsd-3-clause.txt BSD 3-Clause
- * Copyright (c) 2011, Terrence Lee <kill889@gmail.com>
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in the
- *       documentation and/or other materials provided with the distribution.
- *     * Neither the name of the <organization> nor the
- *       names of its contributors may be used to endorse or promote products
- *       derived from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
- * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-export default function gitGraph(canvas, rawGraphList, config) {
-  if (!canvas.getContext) {
-    return;
-  }
-
-  if (typeof config === 'undefined') {
-    config = {
-      unitSize: 20,
-      lineWidth: 3,
-      nodeRadius: 4
-    };
-  }
-
-  const flows = [];
-  const graphList = [];
-
-  const ctx = canvas.getContext('2d');
-
-  const devicePixelRatio = window.devicePixelRatio || 1;
-  const backingStoreRatio = ctx.webkitBackingStorePixelRatio
-                          || ctx.mozBackingStorePixelRatio
-                          || ctx.msBackingStorePixelRatio
-                          || ctx.oBackingStorePixelRatio
-                          || ctx.backingStorePixelRatio || 1;
-
-  const ratio = devicePixelRatio / backingStoreRatio;
-
-  const init = function () {
-    let maxWidth = 0;
-    let i;
-    const l = rawGraphList.length;
-    let row;
-    let midStr;
-
-    for (i = 0; i < l; i++) {
-      midStr = rawGraphList[i].replace(/\s+/g, ' ').replace(/^\s+|\s+$/g, '');
-      midStr = midStr.replace(/(--)|(-\.)/g,'-')
-      maxWidth = Math.max(midStr.replace(/(_|\s)/g, '').length, maxWidth);
-
-      row = midStr.split('');
-
-      graphList.unshift(row);
-    }
-
-    const width = maxWidth * config.unitSize;
-    const height = graphList.length * config.unitSize;
-
-    canvas.width = width * ratio;
-    canvas.height = height * ratio;
-
-    canvas.style.width = `${width}px`;
-    canvas.style.height = `${height}px`;
-
-    ctx.lineWidth = config.lineWidth;
-    ctx.lineJoin = 'round';
-    ctx.lineCap = 'round';
-
-    ctx.scale(ratio, ratio);
-  };
-
-  const genRandomStr = function () {
-    const chars = '0123456789ABCDEF';
-    const stringLength = 6;
-    let randomString = '', rnum, i;
-    for (i = 0; i < stringLength; i++) {
-      rnum = Math.floor(Math.random() * chars.length);
-      randomString += chars.substring(rnum, rnum + 1);
-    }
-
-    return randomString;
-  };
-
-  const findFlow = function (id) {
-    let i = flows.length;
-
-    while (i-- && flows[i].id !== id);
-
-    return i;
-  };
-
-  const findColomn = function (symbol, row) {
-    let i = row.length;
-
-    while (i-- && row[i] !== symbol);
-
-    return i;
-  };
-
-  const findBranchOut = function (row) {
-    if (!row) {
-      return -1;
-    }
-
-    let i = row.length;
-
-    while (i--
-      && !(row[i - 1] && row[i] === '/' && row[i - 1] === '|')
-      && !(row[i - 2] && row[i] === '_' && row[i - 2] === '|'));
-
-    return i;
-  };
-
-  const findLineBreak = function (row) {
-    if (!row) {
-      return -1;
-    }
-
-    let i = row.length;
-
-    while (i--
-    && !(row[i - 1] && row[i - 2] && row[i] === ' ' && row[i - 1] === '|' && row[i - 2] === '_'));
-
-    return i;
-  };
-
-  const genNewFlow = function () {
-    let newId;
-
-    do {
-      newId = genRandomStr();
-    } while (findFlow(newId) !== -1);
-
-    return { id: newId, color: `#${newId}` };
-  };
-
-  // Draw methods
-  const drawLine = function (moveX, moveY, lineX, lineY, color) {
-    ctx.strokeStyle = color;
-    ctx.beginPath();
-    ctx.moveTo(moveX, moveY);
-    ctx.lineTo(lineX, lineY);
-    ctx.stroke();
-  };
-
-  const drawLineRight = function (x, y, color) {
-    drawLine(x, y + config.unitSize / 2, x + config.unitSize, y + config.unitSize / 2, color);
-  };
-
-  const drawLineUp = function (x, y, color) {
-    drawLine(x, y + config.unitSize / 2, x, y - config.unitSize / 2, color);
-  };
-
-  const drawNode = function (x, y, color) {
-    ctx.strokeStyle = color;
-
-    drawLineUp(x, y, color);
-
-    ctx.beginPath();
-    ctx.arc(x, y, config.nodeRadius, 0, Math.PI * 2, true);
-    ctx.fill();
-  };
-
-  const drawLineIn = function (x, y, color) {
-    drawLine(x + config.unitSize, y + config.unitSize / 2, x, y - config.unitSize / 2, color);
-  };
-
-  const drawLineOut = function (x, y, color) {
-    drawLine(x, y + config.unitSize / 2, x + config.unitSize, y - config.unitSize / 2, color);
-  };
-
-  const draw = function (graphList) {
-    let colomn, colomnIndex, prevColomn, condenseIndex, breakIndex = -1;
-    let x, y;
-    let color;
-    let nodePos;
-    let tempFlow;
-    let prevRowLength = 0;
-    let flowSwapPos = -1;
-    let lastLinePos;
-    let i, l;
-    let condenseCurrentLength, condensePrevLength = 0;
-
-    let inlineIntersect = false;
-
-    // initiate color array for first row
-    for (i = 0, l = graphList[0].length; i < l; i++) {
-      if (graphList[0][i] !== '_' && graphList[0][i] !== ' ') {
-        flows.push(genNewFlow());
-      }
-    }
-
-    y = (canvas.height / ratio) - config.unitSize * 0.5;
-
-    // iterate
-    for (i = 0, l = graphList.length; i < l; i++) {
-      x = config.unitSize * 0.5;
-
-      const currentRow = graphList[i];
-      const nextRow = graphList[i + 1];
-      const prevRow = graphList[i - 1];
-
-      flowSwapPos = -1;
-
-      condenseCurrentLength = currentRow.filter((val) => {
-        return (val !== ' ' && val !== '_');
-      }).length;
-
-      // pre process begin
-      // use last row for analysing
-      if (prevRow) {
-        if (!inlineIntersect) {
-          // intersect might happen
-          for (colomnIndex = 0; colomnIndex < prevRowLength; colomnIndex++) {
-            if (prevRow[colomnIndex + 1]
-              && (prevRow[colomnIndex] === '/' && prevRow[colomnIndex + 1] === '|')
-              || ((prevRow[colomnIndex] === '_' && prevRow[colomnIndex + 1] === '|')
-              && (prevRow[colomnIndex + 2] === '/'))) {
-              flowSwapPos = colomnIndex;
-
-              // swap two flow
-              tempFlow = { id: flows[flowSwapPos].id, color: flows[flowSwapPos].color };
-
-              flows[flowSwapPos].id = flows[flowSwapPos + 1].id;
-              flows[flowSwapPos].color = flows[flowSwapPos + 1].color;
-
-              flows[flowSwapPos + 1].id = tempFlow.id;
-              flows[flowSwapPos + 1].color = tempFlow.color;
-            }
-          }
-        }
-
-        if (condensePrevLength < condenseCurrentLength
-          && ((nodePos = findColomn('*', currentRow)) !== -1 // eslint-disable-line no-cond-assign
-          && (findColomn('_', currentRow) === -1))) {
-          flows.splice(nodePos - 1, 0, genNewFlow());
-        }
-
-        if (prevRowLength > currentRow.length
-          && (nodePos = findColomn('*', prevRow)) !== -1) { // eslint-disable-line no-cond-assign
-          if (findColomn('_', currentRow) === -1
-            && findColomn('/', currentRow) === -1
-            && findColomn('\\', currentRow) === -1) {
-            flows.splice(nodePos + 1, 1);
-          }
-        }
-      } // done with the previous row
-
-      prevRowLength = currentRow.length; // store for next round
-      colomnIndex = 0; // reset index
-      condenseIndex = 0;
-      condensePrevLength = 0;
-      breakIndex = -1; // reset break index
-      while (colomnIndex < currentRow.length) {
-        colomn = currentRow[colomnIndex];
-
-        if (colomn !== ' ' && colomn !== '_') {
-          ++condensePrevLength;
-        }
-
-        // check and fix line break in next row
-        if (colomn === '/' && currentRow[colomnIndex - 1] && currentRow[colomnIndex - 1] === '|') {
-          /* eslint-disable-next-line */
-          if ((breakIndex = findLineBreak(nextRow)) !== -1) {
-            nextRow.splice(breakIndex, 1);
-          }
-        }
-        // if line break found replace all '/' with '|' after breakIndex in previous row
-        if (breakIndex !== -1 && colomn === '/' && colomnIndex > breakIndex) {
-          currentRow[colomnIndex] = '|';
-          colomn = '|';
-        }
-
-        if (colomn === ' '
-          && currentRow[colomnIndex + 1]
-          && currentRow[colomnIndex + 1] === '_'
-          && currentRow[colomnIndex - 1]
-          && currentRow[colomnIndex - 1] === '|') {
-          currentRow.splice(colomnIndex, 1);
-
-          currentRow[colomnIndex] = '/';
-          colomn = '/';
-        }
-
-        // create new flow only when no intersect happened
-        if (flowSwapPos === -1
-          && colomn === '/'
-          && currentRow[colomnIndex - 1]
-          && currentRow[colomnIndex - 1] === '|') {
-          flows.splice(condenseIndex, 0, genNewFlow());
-        }
-
-        // change \ and / to | when it's in the last position of the whole row
-        if (colomn === '/' || colomn === '\\') {
-          if (!(colomn === '/' && findBranchOut(nextRow) === -1)) {
-            /* eslint-disable-next-line */
-            if ((lastLinePos = Math.max(findColomn('|', currentRow),
-              findColomn('*', currentRow))) !== -1
-              && (lastLinePos < colomnIndex - 1)) {
-              while (currentRow[++lastLinePos] === ' ');
-
-              if (lastLinePos === colomnIndex) {
-                currentRow[colomnIndex] = '|';
-              }
-            }
-          }
-        }
-
-        if (colomn === '*'
-          && prevRow
-          && prevRow[condenseIndex + 1] === '\\') {
-          flows.splice(condenseIndex + 1, 1);
-        }
-
-        if (colomn !== ' ') {
-          ++condenseIndex;
-        }
-
-        ++colomnIndex;
-      }
-
-      condenseCurrentLength = currentRow.filter((val) => {
-        return (val !== ' ' && val !== '_');
-      }).length;
-
-      colomnIndex = 0;
-
-      // a little inline analysis and draw process
-      while (colomnIndex < currentRow.length) {
-        colomn = currentRow[colomnIndex];
-        prevColomn = currentRow[colomnIndex - 1];
-
-        if (currentRow[colomnIndex] === ' ') {
-          currentRow.splice(colomnIndex, 1);
-          x += config.unitSize;
-
-          continue;
-        }
-
-        // inline intersect
-        if ((colomn === '_' || colomn === '/')
-          && currentRow[colomnIndex - 1] === '|'
-          && currentRow[colomnIndex - 2] === '_') {
-          inlineIntersect = true;
-
-          tempFlow = flows.splice(colomnIndex - 2, 1)[0];
-          flows.splice(colomnIndex - 1, 0, tempFlow);
-          currentRow.splice(colomnIndex - 2, 1);
-
-          colomnIndex -= 1;
-        } else {
-          inlineIntersect = false;
-        }
-
-        if (colomn === '|' && currentRow[colomnIndex - 1] && currentRow[colomnIndex - 1] === '\\') {
-          flows.splice(colomnIndex, 0, genNewFlow());
-        }
-
-        color = flows[colomnIndex].color;
-
-        switch (colomn) {
-          case '-':
-          case '_':
-            drawLineRight(x, y, color);
-
-            x += config.unitSize;
-            break;
-
-          case '*':
-            drawNode(x, y, color);
-            break;
-
-          case '|':
-            if (prevColomn && prevColomn === '\\') {
-              x += config.unitSize;
-            }
-            drawLineUp(x, y, color);
-            break;
-
-          case '/':
-            if (prevColomn
-              && (prevColomn === '/'
-              || prevColomn === ' ')) {
-              x -= config.unitSize;
-            }
-
-            drawLineOut(x, y, color);
-
-            x += config.unitSize;
-            break;
-
-          case '\\':
-            drawLineIn(x, y, color);
-            break;
-        }
-
-        ++colomnIndex;
-      }
-
-      y -= config.unitSize;
-    }
-
-    // do some clean up
-    if (flows.length > condenseCurrentLength) {
-      flows.splice(condenseCurrentLength, flows.length - condenseCurrentLength);
-    }
-  };
-
-  init();
-  draw(graphList);
-}
-// @end-license