fix: better filtering of support files (cypress-io#177)

bahmutov · rndmerle · commit 7ae74425038e · 2020-04-26T01:50:58.000+02:00
* add filtering example with support files

* working example

* run example job on CI

* start the server before testing

* update support file filtering
diff --git a/.circleci/config.yml b/.circleci/config.yml
@@ -209,7 +209,6 @@ workflows:
             - run:
                 command: npx nyc report --check-coverage true --lines 100
                 working_directory: examples/same-folder
-            # how to fail if the specific file coverage is not found?!
             - run:
                 command: npx nyc report --check-coverage true --lines 100 --include unit-utils.js
                 working_directory: examples/same-folder
@@ -221,6 +220,37 @@ workflows:
                   node ../../scripts/only-covered main.js unit-utils.js
                 working_directory: examples/same-folder
 
+      - cypress/run:
+          attach-workspace: true
+          name: example-support-files
+          requires:
+            - cypress/install
+          # there are no jobs to follow this one
+          # so no need to save the workspace files (saves time)
+          no-workspace: true
+          start: npm start --prefix examples/support-files
+          wait-on: 'http://localhost:1234'
+          command: npx cypress run --project examples/support-files
+          # store screenshots and videos
+          store_artifacts: true
+          post-steps:
+            - run: cat examples/support-files/.nyc_output/out.json
+            # store the created coverage report folder
+            # you can click on it in the CircleCI UI
+            # to see live static HTML site
+            - store_artifacts:
+                path: examples/support-files/coverage
+            # make sure the examples captures 100% of code
+            - run:
+                command: npx nyc report --check-coverage true --lines 100
+                working_directory: examples/support-files
+            - run:
+                name: Check code coverage 📈
+                command: |
+                  node ../../scripts/check-coverage main.js
+                  node ../../scripts/only-covered main.js
+                working_directory: examples/support-files
+
       - publish:
           filters:
             branches:
@@ -235,3 +265,4 @@ workflows:
             - example-before-all-visit
             - example-ts-example
             - example-same-folder
+            - example-support-files
diff --git a/examples/support-files/.babelrc b/examples/support-files/.babelrc
@@ -0,0 +1,3 @@
+{
+  "plugins": ["istanbul"]
+}
diff --git a/examples/support-files/README.md b/examples/support-files/README.md
@@ -0,0 +1,3 @@
+# example: support-files
+
+Filtering out support files
diff --git a/examples/support-files/cypress.json b/examples/support-files/cypress.json
@@ -0,0 +1,5 @@
+{
+  "fixturesFolder": false,
+  "pluginsFile": "cypress/plugins/index.js",
+  "baseUrl": "http://localhost:1234"
+}
diff --git a/examples/support-files/cypress/integration/spec.js b/examples/support-files/cypress/integration/spec.js
@@ -0,0 +1,5 @@
+/// <reference types="cypress" />
+it('works', () => {
+  cy.visit('/')
+  cy.contains('Page body')
+})
diff --git a/examples/support-files/cypress/plugins/index.js b/examples/support-files/cypress/plugins/index.js
@@ -0,0 +1,4 @@
+module.exports = (on, config) => {
+  on('task', require('../../../../task'))
+  on('file:preprocessor', require('../../../../use-babelrc'))
+}
diff --git a/examples/support-files/cypress/support/commands.js b/examples/support-files/cypress/support/commands.js
@@ -0,0 +1,2 @@
+import '../../../../support'
+console.log('this is commands file')
diff --git a/examples/support-files/cypress/support/index.js b/examples/support-files/cypress/support/index.js
@@ -0,0 +1 @@
+require('./commands')
diff --git a/examples/support-files/index.html b/examples/support-files/index.html
@@ -0,0 +1,13 @@
+<body>
+  Page body
+  <script src="main.js"></script>
+  <script>
+    // use functions creates in "main.js"
+    if (add(2, 3) !== 5) {
+      throw new Error('wrong addition')
+    }
+    if (sub(2, 3) !== -1) {
+      throw new Error('wrong subtraction')
+    }
+  </script>
+</body>
diff --git a/examples/support-files/main.js b/examples/support-files/main.js
@@ -0,0 +1,3 @@
+window.add = (a, b) => a + b
+
+window.sub = (a, b) => a - b
diff --git a/examples/support-files/package.json b/examples/support-files/package.json
@@ -0,0 +1,12 @@
+{
+  "name": "example-support-files",
+  "description": "Filtering out support files",
+  "devDependencies": {
+    "@babel/core": "7.9.0"
+  },
+  "scripts": {
+    "start": "../../node_modules/.bin/parcel serve index.html",
+    "cy:open": "../../node_modules/.bin/cypress open",
+    "dev": "../../node_modules/.bin/start-test 1234 cy:open"
+  }
+}
diff --git a/support.js b/support.js
@@ -7,7 +7,9 @@
 const sendCoverage = (coverage, pathname = '/') => {
   logMessage(`Saving code coverage for **${pathname}**`)
 
-  const appCoverageOnly = filterSpecsFromCoverage(coverage)
+  const withoutSpecs = filterSpecsFromCoverage(coverage)
+  const appCoverageOnly = filterSupportFilesFromCoverage(withoutSpecs)
+
   // stringify coverage object for speed
   cy.task('combineCoverage', JSON.stringify(appCoverageOnly), {
     log: false
@@ -23,23 +25,49 @@ const logMessage = s => {
   cy.log(`${s} \`[@cypress/code-coverage]\``)
 }
 
-const filterSpecsFromCoverage = totalCoverage => {
-  // remove coverage for the spec files themselves,
-  // only keep "external" application source file coverage
+/**
+ * Removes support file from the coverage object.
+ * If there are more files loaded from support folder, also removes them
+ */
+const filterSupportFilesFromCoverage = totalCoverage => {
   const integrationFolder = Cypress.config('integrationFolder')
   const supportFile = Cypress.config('supportFile')
+  const supportFolder = Cypress.config('supportFolder')
+
+  const isSupportFile = filename => filename === supportFile
+
+  let coverage = Cypress._.omitBy(totalCoverage, (fileCoverage, filename) =>
+    isSupportFile(filename)
+  )
+
+  // check the edge case
+  //   if we have files from support folder AND the support folder is not same
+  //   as the integration, or its prefix (this might remove all app source files)
+  //   then remove all files from the support folder
+  if (!integrationFolder.startsWith(supportFolder)) {
+    // remove all covered files from support folder
+    coverage = Cypress._.omitBy(totalCoverage, (fileCoverage, filename) =>
+      filename.startsWith(supportFolder)
+    )
+  }
+  return coverage
+}
+
+/**
+ * remove coverage for the spec files themselves,
+ * only keep "external" application source file coverage
+ */
+const filterSpecsFromCoverage = totalCoverage => {
+  const integrationFolder = Cypress.config('integrationFolder')
   const testFilePattern = Cypress.config('testFiles')
   const isUsingDefaultTestPattern = testFilePattern === '**/*.*'
 
   const isInIntegrationFolder = filename =>
     filename.startsWith(integrationFolder)
   const isTestFile = filename => Cypress.minimatch(filename, testFilePattern)
-  const isSupportFile = filename => filename === supportFile
 
-  const isA = (fileCoverge, filename) =>
-    isInIntegrationFolder(filename) || isSupportFile(filename)
-  const isB = (fileCoverge, filename) =>
-    isTestFile(filename) || isSupportFile(filename)
+  const isA = (fileCoverge, filename) => isInIntegrationFolder(filename)
+  const isB = (fileCoverge, filename) => isTestFile(filename)
 
   const isTestFileFilter = isUsingDefaultTestPattern ? isA : isB
 

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+{`
	`2`	`+ "plugins": ["istanbul"]`
	`3`	`+}`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+# example: support-files`
	`2`	`+`
	`3`	`+Filtering out support files`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	`+import '../../../../support'`
	`2`	`+console.log('this is commands file')`
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+window.add = (a, b) => a + b`
	`2`	`+`
	`3`	`+window.sub = (a, b) => a - b`