Lessons
Explore all newline lessons
lesson
How to Test Custom ESLint Linting Rules With ASTPractical Abstract Syntax TreesTesting custom ESLint linting rules to verify they work as expected
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How to Unit Test jscodeshift Transforms With ts-jestPractical Abstract Syntax TreesCreate tests for jscodeshift transforms for a faster feedback loop
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How to Use ESLint to Create AST Rules With Babel TraversePractical Abstract Syntax TreesUse ESLint to create the same linting rule for the code with less boilerplate
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How to Ensure Codebase is Up to Date With Linting RulesPractical Abstract Syntax TreesImplement a linting rule to prevent the code we just transformed from being reintroduced in the future
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How to Create Codemods Using jscodeshiftPractical Abstract Syntax TreesUsing jscodeshift to make the same code transformations with less boilerplate
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How to Mutate an AST and Automatically Replace Code ComponentsPractical Abstract Syntax TreesTransforming code in place by mutating an AST
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When to Use Abstract Syntax Tree Tooling to Refactor at ScalePractical Abstract Syntax TreesA rough formula to determine when to use AST-based tooling
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How to Add a Component and Update an ASTPractical Abstract Syntax TreesIntroduce a shared Button component to replace all existing button elements
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How to Audit Your Code With AST ProgrammingPractical Abstract Syntax TreesCreate a custom script to audit a codebase
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Add Type Safety and Prevent Runtime Errors With ASTPractical Abstract Syntax TreesSee how types can surface runtime errors
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Traversing an AST With Babel TraversePractical Abstract Syntax TreesProgrammatically traverse an AST and visit arbitrary nodes
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How to Generate a JavaScript AST With Babel PluginsPractical Abstract Syntax TreesExploring tools to convert (or parse) JavaScript into a real AST