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authorPatrick Williams <patrick@stwcx.xyz>2022-12-08 15:13:13 +0300
committerPatrick Williams <patrick@stwcx.xyz>2022-12-08 15:13:13 +0300
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downloadwebui-vue-7385e139b0c9efca7430458cee982e63e282f4ae.tar.xz
prettier: re-format
Prettier is enabled in openbmc-build-scripts on Markdown, JSON, and YAML files to have consistent formatting for these file types. Re-run the formatter on the whole repository. Change-Id: I2804ee3ab5ff6bcbf986b028db2fafec8e616779 Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
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index b8ca4533..76183768 100644
--- a/docs/guide/unit-testing/readme.md
+++ b/docs/guide/unit-testing/readme.md
@@ -1,19 +1,20 @@
# Unit Testing
- The goal of a unit test is to improve code quality and assure future
- development or refactoring does not result in broken builds and functionality.
- Tests that require consistent updating when refactoring code are likely tightly
- coupled to the internals of the component.
-
- > Writing unit tests is a constant struggle between writing enough tests and
- > not writing too many. I call this the unit testing Goldilocks rule—not too
- > many, not too few, but just enough. Thousands of tests for a small
- > application can be as damaging to development time as no tests.
- >
- > -- <cite>Ed Yerburgh, Testing Vue Applications (New York: Manning
- > Publications, 2019)</cite>
+The goal of a unit test is to improve code quality and assure future development
+or refactoring does not result in broken builds and functionality. Tests that
+require consistent updating when refactoring code are likely tightly coupled to
+the internals of the component.
+
+> Writing unit tests is a constant struggle between writing enough tests and not
+> writing too many. I call this the unit testing Goldilocks rule—not too many,
+> not too few, but just enough. Thousands of tests for a small application can
+> be as damaging to development time as no tests.
+>
+> -- <cite>Ed Yerburgh, Testing Vue Applications (New York: Manning
+> Publications, 2019)</cite>
## Test Libraries
+
The OpenBMC Web UI unit test framework uses the Jest test runner and relies on
the following libraries:
@@ -21,18 +22,20 @@ the following libraries:
- @vue/test-utils
## Test specification location and naming conventions
+
- Create the test files in the /tests/unit directory
- The naming convention is to replicate the folder and component name
### Examples
+
- The AppHeader.vue single-file component's (SFC) spec file is named
`AppHeader.spec.js`
- Create a global component like `PageSection.vue` in the `/tests/global`
directory with the name `PageSection.spec.js`
-- Create a mixin like BVToastMixin in the `/tests/mixins` directory with the
+- Create a mixin like BVToastMixin in the `/tests/mixins` directory with the
name `BVToastMixin.spec.js` Running Tests
- ## Running Tests
+## Running Tests
The `test:unit` script will run all the test suites. Until the integration of
the test script with the continuous integration tool is complete, it needs to be
@@ -40,8 +43,8 @@ run manually before pushing up code for review. If you are working on fixing a
test that is failing, follow the guidelines for debugging a failed tests or
fixing failed snapshot tests.
-
### Debugging a failed test
+
The `test:unit:debugger` script will help to debug failing tests using the
Chrome Developer Tools. To debug a test:
@@ -50,19 +53,21 @@ Chrome Developer Tools. To debug a test:
1. Open the Chrome browser and go to `chrome://inspect`
### Fixing failed snapshot tests
+
The `test:update` script will update snapshot tests. If the UI has changed and
the snapshot tests are failing, after manually verifying the UI changes, run the
update script to update the snapshots. Running `test:update` can be dangerous,
as it will update all snapshot tests.
It is critical to verify all snapshot tests before running the update script.
-The easiest way is to run the unit test in watch mode, `npm run test:unit --
---watch` and verify each snapshot.
+The easiest way is to run the unit test in watch mode,
+`npm run test:unit -- --watch` and verify each snapshot.
## Guidelines
+
- Avoid coupling test code to source code when testing functionality
- - If test cases fail during refactoring, the test case may be tightly
- coupled with the application structure.
+ - If test cases fail during refactoring, the test case may be tightly coupled
+ with the application structure.
- A test should not break if the functionality it tests has not changed
- To maintain test readability, only pass in the data needed for the test to
work in your mock object
@@ -76,13 +81,15 @@ The easiest way is to run the unit test in watch mode, `npm run test:unit --
## Components
### What to test
+
1. Test the function's inputs and outputs
- - Test only dynamically generated output
- - Test only output that is part of the component contract
+ - Test only dynamically generated output
+ - Test only output that is part of the component contract
1. Test any side-effects
1. Test correct rendering using a snapshot test
### What not to test
+
1. Don't test third-party functionality
1. Don't test the internals of your components or that specific functions are
called. This can lead to unnecessary refactoring.
@@ -91,6 +98,7 @@ The easiest way is to run the unit test in watch mode, `npm run test:unit --
1. Static components do not need unit tests, use snapshot testing
### Strategy
+
1. Define a component contract that is based upon the component API
1. Create smaller functions with a specific purpose to make testing easier
1. Test the component API by writing tests first and then writing code to fix
@@ -99,6 +107,7 @@ The easiest way is to run the unit test in watch mode, `npm run test:unit --
visual testing
### Snapshot Testing
+
A snapshot test is a comparison of the code from two different points in time.
When the view is rendering as expected, a snapshot is taken and when the test
suite is run, this snapshot is compared to the current code to make sure nothing
@@ -114,60 +123,68 @@ presentational layer is complete and validated.
There are two testing strategies for testing a Vuex store, which include testing
store parts separately or testing a running store instance. Each strategy has
its pros and cons. Given the size of the store and the number of developers that
-could potentially contribute to the project, the suggested strategy is to `test
-store parts separately`.
+could potentially contribute to the project, the suggested strategy is to
+`test store parts separately`.
### Testing Store Parts Separately
+
Testing the parts separately is easy since each of the parts is a JavaScript
function. Store parts to test include `actions`, `getters`, and `mutations`.
#### Actions
+
Since HTTP calls should never be used in a test, actions require extreme
mocking. Mocking tests rely on assumptions and can lead to faulty tests.
#### Getters
+
Getters are JavaScript functions that return an output. These are basic
functions that may not require testing unless there is getter logic. Any logic
in a getter should be tested.
#### Mutations
+
Mutations are JavaScript functions that mutate the store state. These are basic
functions that may not require testing unless there is mutation logic. Any logic
in a mutation should be tested.
#### Pros
+
- Easier to debug
- Smaller tests
#### Cons
+
- Requires extreme mocking when testing actions
- Tightly coupled with implementation details
- More maintenance required when refactoring
### Testing Store Instance
+
- Uses mutations and actions as inputs
- State is the output
- Requires the use of `localVue` when creating the store to avoid leaky tests
#### Pros
+
- Avoids mocking and brittle tests
- Refactoring does not break test unless contract changes
#### Cons
+
- Debugging is more difficult
## Vue Router
+
- Our current structure does not warrant testing the vue router
- If there is logic used for creating `RouteLink` items, we should unit test
that functionality, which requires stubbing
- When testing a vue router, it is important to use localVue
-
[Vuex Testing](https://vuex.vuejs.org/guide/testing.html)
## Resources
+
- [Vue Test Utils](https://vue-test-utils.vuejs.org/)
-- [Knowing What To Test — Vue Component Unit
- Testing](https://vuejsdevelopers.com/2019/08/26/vue-what-to-unit-test-components/)
-- [How to unit test a vuex
- Store](https://www.dev-tips-and-tricks.com/how-to-unit-test-a-vuex-store) \ No newline at end of file
+- [Knowing What To Test — Vue Component Unit Testing](https://vuejsdevelopers.com/2019/08/26/vue-what-to-unit-test-components/)
+- [How to unit test a vuex Store](https://www.dev-tips-and-tricks.com/how-to-unit-test-a-vuex-store)