fix(types): components.d.ts type resolution for duplicate types (#3337)

this commit updates the type resolution of types used by components when
generating a `components.d.ts` file. types that have been deduplicated
are now piped to functions used to generate the types for class members
that are decorated with `@Prop()`, `@Event()`, and `@Method()`, and used
when generating the types for each.

src/compiler/types/generate-app-types.ts

@@ -77,7 +77,7 @@ const generateComponentTypesFile = (config: d.Config, buildCtx: d.BuildCtx, areT
      * grow as more components (with additional types) are processed.
      */
     typeImportData = updateReferenceTypeImports(typeImportData, allTypes, cmp, cmp.sourceFilePath);
-    return generateComponentTypes(cmp, areTypesInternal);
+    return generateComponentTypes(cmp, typeImportData, areTypesInternal);
   });
 
   c.push(COMPONENTS_DTS_HEADER);

src/compiler/types/generate-component-types.ts

@@ -7,17 +7,22 @@ import { generatePropTypes } from './generate-prop-types';
 /**
  * Generate a string based on the types that are defined within a component
  * @param cmp the metadata for the component that a type definition string is generated for
+ * @param typeImportData locally/imported/globally used type names, which may be used to prevent naming collisions
  * @param areTypesInternal `true` if types being generated are for a project's internal purposes, `false` otherwise
  * @returns the generated types string alongside additional metadata
  */
-export const generateComponentTypes = (cmp: d.ComponentCompilerMeta, areTypesInternal: boolean): d.TypesModule => {
+export const generateComponentTypes = (
+  cmp: d.ComponentCompilerMeta,
+  typeImportData: d.TypesImportData,
+  areTypesInternal: boolean
+): d.TypesModule => {
   const tagName = cmp.tagName.toLowerCase();
   const tagNameAsPascal = dashToPascalCase(tagName);
   const htmlElementName = `HTML${tagNameAsPascal}Element`;
 
-  const propAttributes = generatePropTypes(cmp);
-  const methodAttributes = generateMethodTypes(cmp);
-  const eventAttributes = generateEventTypes(cmp);
+  const propAttributes = generatePropTypes(cmp, typeImportData);
+  const methodAttributes = generateMethodTypes(cmp, typeImportData);
+  const eventAttributes = generateEventTypes(cmp, typeImportData);
 
   const componentAttributes = attributesToMultiLineString(
     [...propAttributes, ...methodAttributes],

src/compiler/types/generate-event-types.ts

@@ -1,17 +1,17 @@
 import type * as d from '../../declarations';
 import { getTextDocs, toTitleCase } from '@utils';
+import { updateTypeIdentifierNames } from './stencil-types';
 
 /**
  * Generates the individual event types for all @Event() decorated events in a component
  * @param cmpMeta component runtime metadata for a single component
+ * @param typeImportData locally/imported/globally used type names, which may be used to prevent naming collisions
  * @returns the generated type metadata
  */
-export const generateEventTypes = (cmpMeta: d.ComponentCompilerMeta): d.TypeInfo => {
+export const generateEventTypes = (cmpMeta: d.ComponentCompilerMeta, typeImportData: d.TypesImportData): d.TypeInfo => {
   return cmpMeta.events.map((cmpEvent) => {
     const name = `on${toTitleCase(cmpEvent.name)}`;
-    const type = cmpEvent.complexType.original
-      ? `(event: CustomEvent<${cmpEvent.complexType.original}>) => void`
-      : `CustomEvent`;
+    const type = getEventType(cmpEvent, typeImportData, cmpMeta.sourceFilePath);
     return {
       name,
       type,
@@ -22,3 +22,27 @@ export const generateEventTypes = (cmpMeta: d.ComponentCompilerMeta): d.TypeInfo
     };
   });
 };
+
+/**
+ * Determine the correct type name for all type(s) used by a class member annotated with `@Event()`
+ * @param cmpEvent the compiler metadata for a single `@Event()`
+ * @param typeImportData locally/imported/globally used type names, which may be used to prevent naming collisions
+ * @param componentSourcePath the path to the component on disk
+ * @returns the type associated with a `@Event()`
+ */
+const getEventType = (
+  cmpEvent: d.ComponentCompilerEvent,
+  typeImportData: d.TypesImportData,
+  componentSourcePath: string
+): string => {
+  if (!cmpEvent.complexType.original) {
+    return 'CustomEvent';
+  }
+  const updatedTypeName = updateTypeIdentifierNames(
+    cmpEvent.complexType.references,
+    typeImportData,
+    componentSourcePath,
+    cmpEvent.complexType.original
+  );
+  return `(event: CustomEvent<${updatedTypeName}>) => void`;
+};

src/compiler/types/generate-method-types.ts

@@ -1,18 +1,43 @@
 import type * as d from '../../declarations';
 import { getTextDocs } from '@utils';
+import { updateTypeIdentifierNames } from './stencil-types';
 
 /**
  * Generates the individual event types for all @Method() decorated events in a component
  * @param cmpMeta component runtime metadata for a single component
+ * @param typeImportData locally/imported/globally used type names, which may be used to prevent naming collisions
  * @returns the generated type metadata
  */
-export const generateMethodTypes = (cmpMeta: d.ComponentCompilerMeta): d.TypeInfo => {
+export const generateMethodTypes = (
+  cmpMeta: d.ComponentCompilerMeta,
+  typeImportData: d.TypesImportData
+): d.TypeInfo => {
   return cmpMeta.methods.map((cmpMethod) => ({
     name: cmpMethod.name,
-    type: cmpMethod.complexType.signature,
+    type: getType(cmpMethod, typeImportData, cmpMeta.sourceFilePath),
     optional: false,
     required: false,
     internal: cmpMethod.internal,
     jsdoc: getTextDocs(cmpMethod.docs),
   }));
 };
+
+/**
+ * Determine the correct type name for all type(s) used by a class member annotated with `@Method()`
+ * @param cmpMethod the compiler metadata for a single `@Method()`
+ * @param typeImportData locally/imported/globally used type names, which may be used to prevent naming collisions
+ * @param componentSourcePath the path to the component on disk
+ * @returns the type associated with a `@Method()`
+ */
+function getType(
+  cmpMethod: d.ComponentCompilerMethod,
+  typeImportData: d.TypesImportData,
+  componentSourcePath: string
+): string {
+  return updateTypeIdentifierNames(
+    cmpMethod.complexType.references,
+    typeImportData,
+    componentSourcePath,
+    cmpMethod.complexType.signature
+  );
+}

src/compiler/types/generate-prop-types.ts

@@ -1,16 +1,18 @@
 import type * as d from '../../declarations';
 import { getTextDocs } from '@utils';
+import { updateTypeIdentifierNames } from './stencil-types';
 
 /**
  * Generates the individual event types for all @Prop() decorated events in a component
  * @param cmpMeta component runtime metadata for a single component
+ * @param typeImportData locally/imported/globally used type names, which may be used to prevent naming collisions
  * @returns the generated type metadata
  */
-export const generatePropTypes = (cmpMeta: d.ComponentCompilerMeta): d.TypeInfo => {
+export const generatePropTypes = (cmpMeta: d.ComponentCompilerMeta, typeImportData: d.TypesImportData): d.TypeInfo => {
   return [
     ...cmpMeta.properties.map((cmpProp) => ({
       name: cmpProp.name,
-      type: cmpProp.complexType.original,
+      type: getType(cmpProp, typeImportData, cmpMeta.sourceFilePath),
       optional: cmpProp.optional,
       required: cmpProp.required,
       internal: cmpProp.internal,
@@ -26,3 +28,23 @@ export const generatePropTypes = (cmpMeta: d.ComponentCompilerMeta): d.TypeInfo
     })),
   ];
 };
+
+/**
+ * Determine the correct type name for all type(s) used by a class member annotated with `@Prop()`
+ * @param cmpProp the compiler metadata for a single `@Prop()`
+ * @param typeImportData locally/imported/globally used type names, which may be used to prevent naming collisions
+ * @param componentSourcePath the path to the component on disk
+ * @returns the type associated with a `@Prop()`
+ */
+function getType(
+  cmpProp: d.ComponentCompilerProperty,
+  typeImportData: d.TypesImportData,
+  componentSourcePath: string
+): string {
+  return updateTypeIdentifierNames(
+    cmpProp.complexType.references,
+    typeImportData,
+    componentSourcePath,
+    cmpProp.complexType.original
+  );
+}

src/compiler/types/stencil-types.ts

@@ -1,5 +1,5 @@
 import type * as d from '../../declarations';
-import { dirname, join, relative } from 'path';
+import { dirname, join, relative, resolve } from 'path';
 import { isOutputTargetDistTypes } from '../output-targets/output-utils';
 import { normalizePath } from '@utils';
 
@@ -30,6 +30,81 @@ export const updateStencilTypesImports = (typesDir: string, dtsFilePath: string,
   return dtsContent;
 };
 
+/**
+ * Utility for ensuring that naming collisions do not appear in type declaration files for a component's class members
+ * decorated with @Prop, @Event, and @Method
+ * @param typeReferences all type names used by a component class member
+ * @param typeImportData locally/imported/globally used type names, which may be used to prevent naming collisions
+ * @param sourceFilePath the path to the source file of a component using the type being inspected
+ * @param initialType the name of the type that may be updated
+ * @returns the updated type name, which may be the same as the initial type name provided as an argument to this
+ * function
+ */
+export const updateTypeIdentifierNames = (
+  typeReferences: d.ComponentCompilerTypeReferences,
+  typeImportData: d.TypesImportData,
+  sourceFilePath: string,
+  initialType: string
+): string => {
+  let currentTypeName = initialType;
+
+  // iterate over each of the type references, as there may be >1 reference to inspect
+  for (let typeReference of Object.values(typeReferences)) {
+    const importResolvedFile = getTypeImportPath(typeReference.path, sourceFilePath);
+
+    if (!typeImportData.hasOwnProperty(importResolvedFile)) {
+      continue;
+    }
+
+    for (let typesImportDatumElement of typeImportData[importResolvedFile]) {
+      currentTypeName = updateTypeName(currentTypeName, typesImportDatumElement);
+    }
+  }
+  return currentTypeName;
+};
+
+/**
+ * Determine the path of a given type reference, relative to the path of a source file
+ * @param importResolvedFile the path to the file containing the resolve type. may be absolute or relative
+ * @param sourceFilePath the component source file path to resolve against
+ * @returns the path of the type import
+ */
+const getTypeImportPath = (importResolvedFile: string | undefined, sourceFilePath: string): string => {
+  const isPathRelative = importResolvedFile && importResolvedFile.startsWith('.');
+  if (isPathRelative) {
+    importResolvedFile = resolve(dirname(sourceFilePath), importResolvedFile);
+  }
+
+  return importResolvedFile;
+};
+
+/**
+ * Determine whether the string representation of a type should be replaced with an alias
+ * @param currentTypeName the current string representation of a type
+ * @param typeAlias a type member and a potential different name associated with the type member
+ * @returns the updated string representation of a type. If the type is not updated, the original type name is returned
+ */
+const updateTypeName = (currentTypeName: string, typeAlias: d.TypesMemberNameData): string => {
+  if (!typeAlias.importName) {
+    return currentTypeName;
+  }
+
+  // TODO(STENCIL-419): Update this functionality to no longer use a regex
+  // negative lookahead specifying that quotes that designate a string in JavaScript cannot follow some expression
+  const endingStrChar = '(?!("|\'|`))';
+  /**
+   * A regular expression that looks at type names along a [word boundary](https://www.regular-expressions.info/wordboundaries.html).
+   * This is used as the best approximation for replacing type collisions, as this stage of compilation has only
+   * 'flattened' type information in the form of a String.
+   *
+   * This regex should be expected to capture types that are found in generics, unions, intersections, etc., but not
+   * those in string literals. We do not check for a starting quote (" | ' | `) here as some browsers do not support
+   * negative lookbehind. This works "well enough" until STENCIL-419 is completed.
+   */
+  const typeNameRegex = new RegExp(`${typeAlias.localName}\\b${endingStrChar}`, 'g');
+  return currentTypeName.replace(typeNameRegex, typeAlias.importName);
+};
+
 /**
  * Writes Stencil core typings file to disk for a dist-* output target
  * @param config the Stencil configuration associated with the project being compiled

src/compiler/types/tests/TypesImportData.stub.ts

@@ -0,0 +1,18 @@
+import * as d from '@stencil/core/declarations';
+
+/**
+ * Generates a stub {@link TypesImportData}.
+ * @param overrides a partial implementation of `TypesImportData`. Any provided fields will override the defaults
+ * provided by this function.
+ * @returns the stubbed `TypesImportData`
+ */
+export const stubTypesImportData = (overrides: Partial<d.TypesImportData> = {}): d.TypesImportData => {
+  /**
+   * By design, we do not provide any default values. the keys used in this data structure will be highly dependent on
+   * the tests being written, and providing default values may lead to unexpected behavior when enumerating the returned
+   * stub
+   */
+  const defaults: d.TypesImportData = {};
+
+  return { ...defaults, ...overrides };
+};