[css-typed-om] Test that styleMap.set rejects invalid values.

Currently, our per-property tests only test that styleMap.set accept
valid values. This patch refactors the per-property tests a bit to
also test that we reject invalid values.

Bug: 774887
Change-Id: I41b5c4c1a6dfe6e766ff37fdc1b1f890dfb81aac
Reviewed-on: https://chromium-review.googlesource.com/905523
Commit-Queue: Darren Shen <shend@chromium.org>
Reviewed-by: nainar <nainar@chromium.org>
Cr-Commit-Position: refs/heads/master@{#536021}

css/css-typed-om/the-stylepropertymap/properties/resources/testsuite.js

@@ -1,3 +1,50 @@
+const gTestSyntax = {
+  '0': {
+    description: 'unitless zero',
+    set: true,
+    examples: [
+      new CSSUnitValue(0, 'number'),
+    ],
+  },
+  '<length>': {
+    description: 'a length',
+    get: true,
+    set: true,
+    examples: [
+      new CSSUnitValue(0, 'px'),
+      new CSSUnitValue(-3.14, 'em'),
+      new CSSUnitValue(3.14, 'cm'),
+    ],
+  },
+  '<percentage>': {
+    description: 'a percent',
+    get: true,
+    set: true,
+    examples: [
+      new CSSUnitValue(0, 'percent'),
+      new CSSUnitValue(-3.14, 'percent'),
+      new CSSUnitValue(3.14, 'percent'),
+    ],
+  },
+  '<time>': {
+    description: 'a time',
+    get: true,
+    set: true,
+    examples: [
+      new CSSUnitValue(0, 's'),
+      new CSSUnitValue(-3.14, 'ms'),
+      new CSSUnitValue(3.14, 's'),
+    ],
+  },
+  '<ident>': {
+    description: 'a CSSKeywordValue',
+    set: true,
+    get: true,
+    // user-specified examples
+    examples: null,
+  },
+};
+
 function testGet(propertyName, values, description) {
   test(t => {
     let element = createDivWithStyle(t);
@@ -27,36 +74,42 @@ function testSet(propertyName, values, description) {
   }, `Can set '${propertyName}' to ${description}`);
 }
 
-function testGetSet(propertyName, values, description) {
-  testGet(propertyName, values, description);
-  testSet(propertyName, values, description);
+function testSetInvalid(propertyName, values, description) {
+  test(t => {
+    let element = createDivWithStyle(t);
+    let styleMap = element.attributeStyleMap;
+
+    for (const styleValue of values) {
+      assert_throws(new TypeError(), () => styleMap.set(propertyName, styleValue));
+    }
+  }, `Setting '${propertyName}' to ${description} throws TypeError`);
 }
 
 function runPropertyTests(propertyName, testCases) {
+  let productionsTested = new Set();
+
   for (const testCase of testCases) {
-    if (testCase.specified == '0') {
-      testSet(propertyName, [
-        new CSSUnitValue(0, 'number'),
-      ], 'unitless zero');
-    } else if (testCase.specified === '<length>') {
-      testGetSet(propertyName, [
-        new CSSUnitValue(0, 'px'),
-        new CSSUnitValue(-3.14, 'em'),
-        new CSSUnitValue(3.14, 'cm'),
-      ], 'a length CSSUnitValue');
-    } else if (testCase.specified == '<percentage>') {
-      testGetSet(propertyName, [
-        new CSSUnitValue(0, 'percent'),
-        new CSSUnitValue(-3.14, 'percent'),
-        new CSSUnitValue(3.14, 'percent'),
-      ], 'a percent CSSUnitValue');
-    } else if (testCase.specified == '<ident>') {
-      if (!testCase.examples) {
-        throw new Error('<ident> tests require examples');
-      }
-
-      testGetSet(propertyName, testCase.examples,
-        'a CSSKeywordValue');
+    const syntax = gTestSyntax[testCase.specified];
+    if (!syntax)
+      throw new Error(`'${testCase.specified}' is not a valid production`);
+
+    const examples = testCase.examples || syntax.examples;
+    if (!examples)
+      throw new Error(`'${testCase.specified}' tests require explicit examples`);
+
+    if (syntax.get)
+      testGet(propertyName, examples, syntax.description);
+    if (syntax.set)
+      testSet(propertyName, examples, syntax.description);
+
+    productionsTested.add(testCase.specified);
+  }
+
+  // Also test that styleMap.set rejects invalid CSSStyleValues.
+  for (const [production, syntax] of Object.entries(gTestSyntax)) {
+    if (!productionsTested.has(production)) {
+      if (syntax.set && syntax.examples)
+        testSetInvalid(propertyName, syntax.examples, syntax.description);
     }
   }
 }