Enforce the use, in non-production/test-only mode, of Uint8ClampedArray in all relevant methods in ColorSpace and PDFImage

Since `ColorSpace` now depends on the native clamping of `Uint8ClampedArray`, this patch adds non-production/test-only `assert`s to enforce that the expected TypedArray is used for the output.

These `assert`s are purposely *not* included in PRODUCTION builds since that would break rendering completely, as opposed to "only" displaying some weird colours, when a `Uint8Array` was used. Furthermore, these are mostly added to help catch explicit developer errors when working with the `ColorSpace` and `PDFImage` code.

src/core/colorspace.js

@@ -14,7 +14,7 @@
  */
 
 import {
-  FormatError, info, isString, shadow, unreachable, warn
+  assert, FormatError, info, isString, shadow, unreachable, warn
 } from '../shared/util';
 import { isDict, isName, isStream } from './primitives';
 
@@ -109,6 +109,11 @@ var ColorSpace = (function ColorSpaceClosure() {
      */
     fillRgb(dest, originalWidth, originalHeight, width, height, actualHeight,
             bpc, comps, alpha01) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+               'ColorSpace.fillRgb: Unsupported "dest" type.');
+      }
       var count = originalWidth * originalHeight;
       var rgbBuf = null;
       var numComponentColors = 1 << bpc;
@@ -433,11 +438,21 @@ var AlternateCS = (function AlternateCSClosure() {
   AlternateCS.prototype = {
     getRgb: ColorSpace.prototype.getRgb,
     getRgbItem(src, srcOffset, dest, destOffset) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+               'AlternateCS.getRgbItem: Unsupported "dest" type.');
+      }
       var tmpBuf = this.tmpBuf;
       this.tintFn(src, srcOffset, tmpBuf, 0);
       this.base.getRgbItem(tmpBuf, 0, dest, destOffset);
     },
     getRgbBuffer(src, srcOffset, count, dest, destOffset, bits, alpha01) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+               'AlternateCS.getRgbBuffer: Unsupported "dest" type.');
+      }
       var tintFn = this.tintFn;
       var base = this.base;
       var scale = 1 / ((1 << bits) - 1);
@@ -529,11 +544,21 @@ var IndexedCS = (function IndexedCSClosure() {
   IndexedCS.prototype = {
     getRgb: ColorSpace.prototype.getRgb,
     getRgbItem(src, srcOffset, dest, destOffset) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+               'IndexedCS.getRgbItem: Unsupported "dest" type.');
+      }
       var numComps = this.base.numComps;
       var start = src[srcOffset] * numComps;
       this.base.getRgbBuffer(this.lookup, start, 1, dest, destOffset, 8, 0);
     },
     getRgbBuffer(src, srcOffset, count, dest, destOffset, bits, alpha01) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+               'IndexedCS.getRgbBuffer: Unsupported "dest" type.');
+      }
       var base = this.base;
       var numComps = base.numComps;
       var outputDelta = base.getOutputLength(numComps, alpha01);
@@ -570,10 +595,20 @@ var DeviceGrayCS = (function DeviceGrayCSClosure() {
   DeviceGrayCS.prototype = {
     getRgb: ColorSpace.prototype.getRgb,
     getRgbItem(src, srcOffset, dest, destOffset) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+               'DeviceGrayCS.getRgbItem: Unsupported "dest" type.');
+      }
       let c = src[srcOffset] * 255;
       dest[destOffset] = dest[destOffset + 1] = dest[destOffset + 2] = c;
     },
     getRgbBuffer(src, srcOffset, count, dest, destOffset, bits, alpha01) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+               'DeviceGrayCS.getRgbBuffer: Unsupported "dest" type.');
+      }
       var scale = 255 / ((1 << bits) - 1);
       var j = srcOffset, q = destOffset;
       for (var i = 0; i < count; ++i) {
@@ -606,11 +641,21 @@ var DeviceRgbCS = (function DeviceRgbCSClosure() {
   DeviceRgbCS.prototype = {
     getRgb: ColorSpace.prototype.getRgb,
     getRgbItem(src, srcOffset, dest, destOffset) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+               'DeviceRgbCS.getRgbItem: Unsupported "dest" type.');
+      }
       dest[destOffset] = src[srcOffset] * 255;
       dest[destOffset + 1] = src[srcOffset + 1] * 255;
       dest[destOffset + 2] = src[srcOffset + 2] * 255;
     },
     getRgbBuffer(src, srcOffset, count, dest, destOffset, bits, alpha01) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+               'DeviceRgbCS.getRgbBuffer: Unsupported "dest" type.');
+      }
       if (bits === 8 && alpha01 === 0) {
         dest.set(src.subarray(srcOffset, srcOffset + count * 3), destOffset);
         return;
@@ -692,9 +737,19 @@ var DeviceCmykCS = (function DeviceCmykCSClosure() {
   DeviceCmykCS.prototype = {
     getRgb: ColorSpace.prototype.getRgb,
     getRgbItem(src, srcOffset, dest, destOffset) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+               'DeviceCmykCS.getRgbItem: Unsupported "dest" type.');
+      }
       convertToRgb(src, srcOffset, 1, dest, destOffset);
     },
     getRgbBuffer(src, srcOffset, count, dest, destOffset, bits, alpha01) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+               'DeviceCmykCS.getRgbBuffer: Unsupported "dest" type.');
+      }
       var scale = 1 / ((1 << bits) - 1);
       for (var i = 0; i < count; i++) {
         convertToRgb(src, srcOffset, scale, dest, destOffset);
@@ -786,9 +841,19 @@ var CalGrayCS = (function CalGrayCSClosure() {
   CalGrayCS.prototype = {
     getRgb: ColorSpace.prototype.getRgb,
     getRgbItem(src, srcOffset, dest, destOffset) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+               'CalGrayCS.getRgbItem: Unsupported "dest" type.');
+      }
       convertToRgb(this, src, srcOffset, dest, destOffset, 1);
     },
     getRgbBuffer(src, srcOffset, count, dest, destOffset, bits, alpha01) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+               'CalGrayCS.getRgbBuffer: Unsupported "dest" type.');
+      }
       var scale = 1 / ((1 << bits) - 1);
 
       for (var i = 0; i < count; ++i) {
@@ -1075,9 +1140,19 @@ var CalRGBCS = (function CalRGBCSClosure() {
   CalRGBCS.prototype = {
     getRgb: ColorSpace.prototype.getRgb,
     getRgbItem(src, srcOffset, dest, destOffset) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+               'CalRGBCS.getRgbItem: Unsupported "dest" type.');
+      }
       convertToRgb(this, src, srcOffset, dest, destOffset, 1);
     },
     getRgbBuffer(src, srcOffset, count, dest, destOffset, bits, alpha01) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+              'CalRGBCS.getRgbBuffer: Unsupported "dest" type.');
+      }
       var scale = 1 / ((1 << bits) - 1);
 
       for (var i = 0; i < count; ++i) {
@@ -1218,9 +1293,19 @@ var LabCS = (function LabCSClosure() {
   LabCS.prototype = {
     getRgb: ColorSpace.prototype.getRgb,
     getRgbItem(src, srcOffset, dest, destOffset) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+               'LabCS.getRgbItem: Unsupported "dest" type.');
+      }
       convertToRgb(this, src, srcOffset, false, dest, destOffset);
     },
     getRgbBuffer(src, srcOffset, count, dest, destOffset, bits, alpha01) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(dest instanceof Uint8ClampedArray,
+               'LabCS.getRgbBuffer: Unsupported "dest" type.');
+      }
       var maxVal = (1 << bits) - 1;
       for (var i = 0; i < count; i++) {
         convertToRgb(this, src, srcOffset, maxVal, dest, destOffset);

src/core/image.js

@@ -244,6 +244,11 @@ var PDFImage = (function PDFImageClosure() {
 
   PDFImage.createMask = function({ imgArray, width, height,
                                    imageIsFromDecodeStream, inverseDecode, }) {
+    if (typeof PDFJSDev === 'undefined' ||
+        PDFJSDev.test('!PRODUCTION || TESTING')) {
+      assert(imgArray instanceof Uint8ClampedArray,
+             'PDFImage.createMask: Unsupported "imgArray" type.');
+    }
     // |imgArray| might not contain full data for every pixel of the mask, so
     // we need to distinguish between |computedLength| and |actualLength|.
     // In particular, if inverseDecode is true, then the array we return must
@@ -399,6 +404,11 @@ var PDFImage = (function PDFImageClosure() {
     },
 
     fillOpacity(rgbaBuf, width, height, actualHeight, image) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(rgbaBuf instanceof Uint8ClampedArray,
+               'PDFImage.fillOpacity: Unsupported "rgbaBuf" type.');
+      }
       var smask = this.smask;
       var mask = this.mask;
       var alphaBuf, sw, sh, i, ii, j;
@@ -465,6 +475,11 @@ var PDFImage = (function PDFImageClosure() {
     },
 
     undoPreblend(buffer, width, height) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(buffer instanceof Uint8ClampedArray,
+               'PDFImage.undoPreblend: Unsupported "buffer" type.');
+      }
       var matte = this.smask && this.smask.matte;
       if (!matte) {
         return;
@@ -544,7 +559,8 @@ var PDFImage = (function PDFImageClosure() {
           }
           if (this.needsDecode) {
             // Invert the buffer (which must be grayscale if we reached here).
-            assert(kind === ImageKind.GRAYSCALE_1BPP);
+            assert(kind === ImageKind.GRAYSCALE_1BPP,
+                   'PDFImage.createImageData: The image must be grayscale.');
             var buffer = imgData.data;
             for (var i = 0, ii = buffer.length; i < ii; i++) {
               buffer[i] ^= 0xff;
@@ -610,6 +626,11 @@ var PDFImage = (function PDFImageClosure() {
     },
 
     fillGrayBuffer(buffer) {
+      if (typeof PDFJSDev === 'undefined' ||
+          PDFJSDev.test('!PRODUCTION || TESTING')) {
+        assert(buffer instanceof Uint8ClampedArray,
+               'PDFImage.fillGrayBuffer: Unsupported "buffer" type.');
+      }
       var numComps = this.numComps;
       if (numComps !== 1) {
         throw new FormatError(