update Accessibility gatherer to use Errors for errors

GoogleChrome · Feb 4, 2017 · a9e431d · a9e431d
1 parent f9da435
commit a9e431d
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Showing 11 changed files with 27 additions and 143 deletions.
diff --git a/lighthouse-core/audits/accessibility/axe-audit.js b/lighthouse-core/audits/accessibility/axe-audit.js
@@ -32,7 +32,7 @@ class AxeAudit extends Audit {
    * @return {!AuditResult}
    */
   static audit(artifacts) {
-    const violations = artifacts.Accessibility.violations || [];
+    const violations = artifacts.Accessibility.violations;
     const rule = violations.find(result => result.id === this.meta.name);
 
     return this.generateAuditResult({

diff --git a/lighthouse-core/gather/gatherers/accessibility.js b/lighthouse-core/gather/gatherers/accessibility.js
@@ -47,14 +47,10 @@ function runA11yChecks() {
 }
 
 class Accessibility extends Gatherer {
-  static _errorAccessibility(errorString) {
-    return {
-      raw: undefined,
-      value: undefined,
-      debugString: errorString
-    };
-  }
-
+  /**
+   * @param {!Object} options
+   * @return {!Promise<{violations: !Array}>}
+   */
   afterPass(options) {
     const driver = options.driver;
     const expression = `(function () {
@@ -63,20 +59,14 @@ class Accessibility extends Gatherer {
     })()`;
 
     return driver
-        .evaluateAsync(expression)
-        .then(returnedValue => {
-          if (!returnedValue) {
-            return Accessibility._errorAccessibility('Unable to parse axe results');
-          }
-
-          if (returnedValue.error) {
-            return Accessibility._errorAccessibility(returnedValue.error);
-          }
+      .evaluateAsync(expression)
+      .then(returnedValue => {
+        if (!returnedValue || !Array.isArray(returnedValue.violations)) {
+          throw new Error('Unable to parse axe results' + returnedValue);
+        }
 
-          return returnedValue;
-        }, _ => {
-          return Accessibility._errorAccessibility('Axe results timed out');
-        });
+        return returnedValue;
+      });
   }
 }
 

diff --git a/lighthouse-core/test/audits/accessibility/aria-allowed-attr-test.js b/lighthouse-core/test/audits/accessibility/aria-allowed-attr-test.js
@@ -53,15 +53,4 @@ describe('Accessibility: aria-allowed-attr audit', () => {
     assert.equal(output.rawValue, false);
     assert.equal(output.displayValue, '');
   });
-
-  it('doesn\'t throw an error when violations is undefined', () => {
-    const artifacts = {
-      Accessibility: {
-        violations: undefined
-      }
-    };
-
-    const output = Audit.audit(artifacts);
-    assert.equal(output.description, 'Element aria-* attributes are allowed for this role');
-  });
 });
diff --git a/lighthouse-core/test/audits/accessibility/aria-required-attr-test.js b/lighthouse-core/test/audits/accessibility/aria-required-attr-test.js
@@ -53,16 +53,4 @@ describe('Accessibility: aria-required-attr audit', () => {
     assert.equal(output.rawValue, false);
     assert.equal(output.displayValue, '');
   });
-
-  it('doesn\'t throw an error when violations is undefined', () => {
-    const artifacts = {
-      Accessibility: {
-        violations: undefined
-      }
-    };
-
-    const output = Audit.audit(artifacts);
-    assert.equal(output.description,
-        'Elements with ARIA roles have the required aria-* attributes');
-  });
 });
diff --git a/lighthouse-core/test/audits/accessibility/aria-valid-attr-test.js b/lighthouse-core/test/audits/accessibility/aria-valid-attr-test.js
@@ -53,16 +53,4 @@ describe('Accessibility: aria-valid-attr audit', () => {
     assert.equal(output.rawValue, false);
     assert.equal(output.displayValue, '');
   });
-
-  it('doesn\'t throw an error when violations is undefined', () => {
-    const artifacts = {
-      Accessibility: {
-        violations: undefined
-      }
-    };
-
-    const output = Audit.audit(artifacts);
-    assert.equal(output.description,
-        'Element aria-* attributes are valid and not misspelled or non-existent.');
-  });
 });
diff --git a/lighthouse-core/test/audits/accessibility/aria-valid-attr-value-test.js b/lighthouse-core/test/audits/accessibility/aria-valid-attr-value-test.js
@@ -53,15 +53,4 @@ describe('Accessibility: aria-valid-attr-value audit', () => {
     assert.equal(output.rawValue, false);
     assert.equal(output.displayValue, '');
   });
-
-  it('doesn\'t throw an error when violations is undefined', () => {
-    const artifacts = {
-      Accessibility: {
-        violations: undefined
-      }
-    };
-
-    const output = Audit.audit(artifacts);
-    assert.equal(output.description, 'Element aria-* attributes have valid values');
-  });
 });
diff --git a/lighthouse-core/test/audits/accessibility/color-contrast-test.js b/lighthouse-core/test/audits/accessibility/color-contrast-test.js
@@ -53,16 +53,4 @@ describe('Accessibility: color-contrast audit', () => {
     assert.equal(output.rawValue, false);
     assert.equal(output.displayValue, '');
   });
-
-  it('doesn\'t throw an error when violations is undefined', () => {
-    const artifacts = {
-      Accessibility: {
-        violations: undefined
-      }
-    };
-
-    const output = Audit.audit(artifacts);
-    assert.equal(output.description,
-        'Background and foreground colors have a sufficient contrast ratio');
-  });
 });
diff --git a/lighthouse-core/test/audits/accessibility/image-alt-test.js b/lighthouse-core/test/audits/accessibility/image-alt-test.js
@@ -53,15 +53,4 @@ describe('Accessibility: image-alt audit', () => {
     assert.equal(output.rawValue, false);
     assert.equal(output.displayValue, '');
   });
-
-  it('doesn\'t throw an error when violations is undefined', () => {
-    const artifacts = {
-      Accessibility: {
-        violations: undefined
-      }
-    };
-
-    const output = Audit.audit(artifacts);
-    assert.equal(output.description, 'Every image element has an alt attribute');
-  });
 });
diff --git a/lighthouse-core/test/audits/accessibility/label-test.js b/lighthouse-core/test/audits/accessibility/label-test.js
@@ -53,15 +53,4 @@ describe('Accessibility: label audit', () => {
     assert.equal(output.rawValue, false);
     assert.equal(output.displayValue, '');
   });
-
-  it('doesn\'t throw an error when violations is undefined', () => {
-    const artifacts = {
-      Accessibility: {
-        violations: undefined
-      }
-    };
-
-    const output = Audit.audit(artifacts);
-    assert.equal(output.description, 'Every form element has a label');
-  });
 });
diff --git a/lighthouse-core/test/audits/accessibility/tabindex-test.js b/lighthouse-core/test/audits/accessibility/tabindex-test.js
@@ -53,15 +53,4 @@ describe('Accessibility: tabindex audit', () => {
     assert.equal(output.rawValue, false);
     assert.equal(output.displayValue, '');
   });
-
-  it('doesn\'t throw an error when violations is undefined', () => {
-    const artifacts = {
-      Accessibility: {
-        violations: undefined
-      }
-    };
-
-    const output = Audit.audit(artifacts);
-    assert.equal(output.description, 'No element has a `tabindex` attribute greater than 0');
-  });
 });
diff --git a/lighthouse-core/test/gather/gatherers/accessibility-test.js b/lighthouse-core/test/gather/gatherers/accessibility-test.js
@@ -27,57 +27,42 @@ describe('Accessibility gatherer', () => {
     accessibilityGather = new AccessibilityGather();
   });
 
-  it('fails gracefully', () => {
+  it('fails if nothing is returned', () => {
     return accessibilityGather.afterPass({
       driver: {
         evaluateAsync() {
           return Promise.resolve();
         }
       }
-    }).then(artifact => {
-      assert.ok(typeof artifact === 'object');
-    });
+    }).then(
+      _ => assert.ok(false),
+      _ => assert.ok(true));
   });
 
-  it('handles driver failure', () => {
-    return accessibilityGather.afterPass({
-      driver: {
-        evaluateAsync() {
-          return Promise.reject('such a fail');
-        }
-      }
-    }).then(artifact => {
-      assert.ok(artifact.debugString);
-    });
-  });
-
-  it('propagates error retrieving the results', () => {
-    const error = 'There was an error.';
+  it('fails if result has no violations array', () => {
     return accessibilityGather.afterPass({
       driver: {
         evaluateAsync() {
           return Promise.resolve({
-            error
+            url: 'https://example.com'
           });
         }
       }
-    }).then(artifact => {
-      assert.ok(artifact.debugString === error);
-    });
+    }).then(
+      _ => assert.ok(false),
+      _ => assert.ok(true));
   });
 
-  it('creates an object for valid results', () => {
+  it('propagates error retrieving the results', () => {
+    const error = 'There was an error.';
     return accessibilityGather.afterPass({
       driver: {
         evaluateAsync() {
-          return Promise.resolve({
-            name: 'a11y'
-          });
+          return Promise.reject(new Error(error));
         }
       }
-    }).then(artifact => {
-      assert.ok(typeof artifact === 'object');
-      assert.equal(artifact.name, 'a11y');
-    });
+    }).then(
+      _ => assert.ok(false),
+      err => assert.ok(err.message.includes(error)));
   });
 });