Docs

1 files changed, 456 insertions, 0 deletions

diff --git a/node_modules/sucrase/dist/esm/CJSImportProcessor.js b/node_modules/sucrase/dist/esm/CJSImportProcessor.js
new file mode 100644
index 0000000..d8b7803
--- /dev/null
+++ b/node_modules/sucrase/dist/esm/CJSImportProcessor.js
@@ -0,0 +1,456 @@
+
+
+
+import {isDeclaration} from "./parser/tokenizer";
+import {ContextualKeyword} from "./parser/tokenizer/keywords";
+import {TokenType as tt} from "./parser/tokenizer/types";
+
+import getImportExportSpecifierInfo from "./util/getImportExportSpecifierInfo";
+import {getNonTypeIdentifiers} from "./util/getNonTypeIdentifiers";
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+/**
+ * Class responsible for preprocessing and bookkeeping import and export declarations within the
+ * file.
+ *
+ * TypeScript uses a simpler mechanism that does not use functions like interopRequireDefault and
+ * interopRequireWildcard, so we also allow that mode for compatibility.
+ */
+export default class CJSImportProcessor {
+   __init() {this.nonTypeIdentifiers = new Set()}
+   __init2() {this.importInfoByPath = new Map()}
+   __init3() {this.importsToReplace = new Map()}
+   __init4() {this.identifierReplacements = new Map()}
+   __init5() {this.exportBindingsByLocalName = new Map()}
+
+  constructor(
+     nameManager,
+     tokens,
+     enableLegacyTypeScriptModuleInterop,
+     options,
+     isTypeScriptTransformEnabled,
+     keepUnusedImports,
+     helperManager,
+  ) {;this.nameManager = nameManager;this.tokens = tokens;this.enableLegacyTypeScriptModuleInterop = enableLegacyTypeScriptModuleInterop;this.options = options;this.isTypeScriptTransformEnabled = isTypeScriptTransformEnabled;this.keepUnusedImports = keepUnusedImports;this.helperManager = helperManager;CJSImportProcessor.prototype.__init.call(this);CJSImportProcessor.prototype.__init2.call(this);CJSImportProcessor.prototype.__init3.call(this);CJSImportProcessor.prototype.__init4.call(this);CJSImportProcessor.prototype.__init5.call(this);}
+
+  preprocessTokens() {
+    for (let i = 0; i < this.tokens.tokens.length; i++) {
+      if (
+        this.tokens.matches1AtIndex(i, tt._import) &&
+        !this.tokens.matches3AtIndex(i, tt._import, tt.name, tt.eq)
+      ) {
+        this.preprocessImportAtIndex(i);
+      }
+      if (
+        this.tokens.matches1AtIndex(i, tt._export) &&
+        !this.tokens.matches2AtIndex(i, tt._export, tt.eq)
+      ) {
+        this.preprocessExportAtIndex(i);
+      }
+    }
+    this.generateImportReplacements();
+  }
+
+  /**
+   * In TypeScript, import statements that only import types should be removed.
+   * This includes `import {} from 'foo';`, but not `import 'foo';`.
+   */
+  pruneTypeOnlyImports() {
+    this.nonTypeIdentifiers = getNonTypeIdentifiers(this.tokens, this.options);
+    for (const [path, importInfo] of this.importInfoByPath.entries()) {
+      if (
+        importInfo.hasBareImport ||
+        importInfo.hasStarExport ||
+        importInfo.exportStarNames.length > 0 ||
+        importInfo.namedExports.length > 0
+      ) {
+        continue;
+      }
+      const names = [
+        ...importInfo.defaultNames,
+        ...importInfo.wildcardNames,
+        ...importInfo.namedImports.map(({localName}) => localName),
+      ];
+      if (names.every((name) => this.shouldAutomaticallyElideImportedName(name))) {
+        this.importsToReplace.set(path, "");
+      }
+    }
+  }
+
+  shouldAutomaticallyElideImportedName(name) {
+    return (
+      this.isTypeScriptTransformEnabled &&
+      !this.keepUnusedImports &&
+      !this.nonTypeIdentifiers.has(name)
+    );
+  }
+
+   generateImportReplacements() {
+    for (const [path, importInfo] of this.importInfoByPath.entries()) {
+      const {
+        defaultNames,
+        wildcardNames,
+        namedImports,
+        namedExports,
+        exportStarNames,
+        hasStarExport,
+      } = importInfo;
+
+      if (
+        defaultNames.length === 0 &&
+        wildcardNames.length === 0 &&
+        namedImports.length === 0 &&
+        namedExports.length === 0 &&
+        exportStarNames.length === 0 &&
+        !hasStarExport
+      ) {
+        // Import is never used, so don't even assign a name.
+        this.importsToReplace.set(path, `require('${path}');`);
+        continue;
+      }
+
+      const primaryImportName = this.getFreeIdentifierForPath(path);
+      let secondaryImportName;
+      if (this.enableLegacyTypeScriptModuleInterop) {
+        secondaryImportName = primaryImportName;
+      } else {
+        secondaryImportName =
+          wildcardNames.length > 0 ? wildcardNames[0] : this.getFreeIdentifierForPath(path);
+      }
+      let requireCode = `var ${primaryImportName} = require('${path}');`;
+      if (wildcardNames.length > 0) {
+        for (const wildcardName of wildcardNames) {
+          const moduleExpr = this.enableLegacyTypeScriptModuleInterop
+            ? primaryImportName
+            : `${this.helperManager.getHelperName("interopRequireWildcard")}(${primaryImportName})`;
+          requireCode += ` var ${wildcardName} = ${moduleExpr};`;
+        }
+      } else if (exportStarNames.length > 0 && secondaryImportName !== primaryImportName) {
+        requireCode += ` var ${secondaryImportName} = ${this.helperManager.getHelperName(
+          "interopRequireWildcard",
+        )}(${primaryImportName});`;
+      } else if (defaultNames.length > 0 && secondaryImportName !== primaryImportName) {
+        requireCode += ` var ${secondaryImportName} = ${this.helperManager.getHelperName(
+          "interopRequireDefault",
+        )}(${primaryImportName});`;
+      }
+
+      for (const {importedName, localName} of namedExports) {
+        requireCode += ` ${this.helperManager.getHelperName(
+          "createNamedExportFrom",
+        )}(${primaryImportName}, '${localName}', '${importedName}');`;
+      }
+      for (const exportStarName of exportStarNames) {
+        requireCode += ` exports.${exportStarName} = ${secondaryImportName};`;
+      }
+      if (hasStarExport) {
+        requireCode += ` ${this.helperManager.getHelperName(
+          "createStarExport",
+        )}(${primaryImportName});`;
+      }
+
+      this.importsToReplace.set(path, requireCode);
+
+      for (const defaultName of defaultNames) {
+        this.identifierReplacements.set(defaultName, `${secondaryImportName}.default`);
+      }
+      for (const {importedName, localName} of namedImports) {
+        this.identifierReplacements.set(localName, `${primaryImportName}.${importedName}`);
+      }
+    }
+  }
+
+  getFreeIdentifierForPath(path) {
+    const components = path.split("/");
+    const lastComponent = components[components.length - 1];
+    const baseName = lastComponent.replace(/\W/g, "");
+    return this.nameManager.claimFreeName(`_${baseName}`);
+  }
+
+   preprocessImportAtIndex(index) {
+    const defaultNames = [];
+    const wildcardNames = [];
+    const namedImports = [];
+
+    index++;
+    if (
+      (this.tokens.matchesContextualAtIndex(index, ContextualKeyword._type) ||
+        this.tokens.matches1AtIndex(index, tt._typeof)) &&
+      !this.tokens.matches1AtIndex(index + 1, tt.comma) &&
+      !this.tokens.matchesContextualAtIndex(index + 1, ContextualKeyword._from)
+    ) {
+      // import type declaration, so no need to process anything.
+      return;
+    }
+
+    if (this.tokens.matches1AtIndex(index, tt.parenL)) {
+      // Dynamic import, so nothing to do
+      return;
+    }
+
+    if (this.tokens.matches1AtIndex(index, tt.name)) {
+      defaultNames.push(this.tokens.identifierNameAtIndex(index));
+      index++;
+      if (this.tokens.matches1AtIndex(index, tt.comma)) {
+        index++;
+      }
+    }
+
+    if (this.tokens.matches1AtIndex(index, tt.star)) {
+      // * as
+      index += 2;
+      wildcardNames.push(this.tokens.identifierNameAtIndex(index));
+      index++;
+    }
+
+    if (this.tokens.matches1AtIndex(index, tt.braceL)) {
+      const result = this.getNamedImports(index + 1);
+      index = result.newIndex;
+
+      for (const namedImport of result.namedImports) {
+        // Treat {default as X} as a default import to ensure usage of require interop helper
+        if (namedImport.importedName === "default") {
+          defaultNames.push(namedImport.localName);
+        } else {
+          namedImports.push(namedImport);
+        }
+      }
+    }
+
+    if (this.tokens.matchesContextualAtIndex(index, ContextualKeyword._from)) {
+      index++;
+    }
+
+    if (!this.tokens.matches1AtIndex(index, tt.string)) {
+      throw new Error("Expected string token at the end of import statement.");
+    }
+    const path = this.tokens.stringValueAtIndex(index);
+    const importInfo = this.getImportInfo(path);
+    importInfo.defaultNames.push(...defaultNames);
+    importInfo.wildcardNames.push(...wildcardNames);
+    importInfo.namedImports.push(...namedImports);
+    if (defaultNames.length === 0 && wildcardNames.length === 0 && namedImports.length === 0) {
+      importInfo.hasBareImport = true;
+    }
+  }
+
+   preprocessExportAtIndex(index) {
+    if (
+      this.tokens.matches2AtIndex(index, tt._export, tt._var) ||
+      this.tokens.matches2AtIndex(index, tt._export, tt._let) ||
+      this.tokens.matches2AtIndex(index, tt._export, tt._const)
+    ) {
+      this.preprocessVarExportAtIndex(index);
+    } else if (
+      this.tokens.matches2AtIndex(index, tt._export, tt._function) ||
+      this.tokens.matches2AtIndex(index, tt._export, tt._class)
+    ) {
+      const exportName = this.tokens.identifierNameAtIndex(index + 2);
+      this.addExportBinding(exportName, exportName);
+    } else if (this.tokens.matches3AtIndex(index, tt._export, tt.name, tt._function)) {
+      const exportName = this.tokens.identifierNameAtIndex(index + 3);
+      this.addExportBinding(exportName, exportName);
+    } else if (this.tokens.matches2AtIndex(index, tt._export, tt.braceL)) {
+      this.preprocessNamedExportAtIndex(index);
+    } else if (this.tokens.matches2AtIndex(index, tt._export, tt.star)) {
+      this.preprocessExportStarAtIndex(index);
+    }
+  }
+
+   preprocessVarExportAtIndex(index) {
+    let depth = 0;
+    // Handle cases like `export let {x} = y;`, starting at the open-brace in that case.
+    for (let i = index + 2; ; i++) {
+      if (
+        this.tokens.matches1AtIndex(i, tt.braceL) ||
+        this.tokens.matches1AtIndex(i, tt.dollarBraceL) ||
+        this.tokens.matches1AtIndex(i, tt.bracketL)
+      ) {
+        depth++;
+      } else if (
+        this.tokens.matches1AtIndex(i, tt.braceR) ||
+        this.tokens.matches1AtIndex(i, tt.bracketR)
+      ) {
+        depth--;
+      } else if (depth === 0 && !this.tokens.matches1AtIndex(i, tt.name)) {
+        break;
+      } else if (this.tokens.matches1AtIndex(1, tt.eq)) {
+        const endIndex = this.tokens.currentToken().rhsEndIndex;
+        if (endIndex == null) {
+          throw new Error("Expected = token with an end index.");
+        }
+        i = endIndex - 1;
+      } else {
+        const token = this.tokens.tokens[i];
+        if (isDeclaration(token)) {
+          const exportName = this.tokens.identifierNameAtIndex(i);
+          this.identifierReplacements.set(exportName, `exports.${exportName}`);
+        }
+      }
+    }
+  }
+
+  /**
+   * Walk this export statement just in case it's an export...from statement.
+   * If it is, combine it into the import info for that path. Otherwise, just
+   * bail out; it'll be handled later.
+   */
+   preprocessNamedExportAtIndex(index) {
+    // export {
+    index += 2;
+    const {newIndex, namedImports} = this.getNamedImports(index);
+    index = newIndex;
+
+    if (this.tokens.matchesContextualAtIndex(index, ContextualKeyword._from)) {
+      index++;
+    } else {
+      // Reinterpret "a as b" to be local/exported rather than imported/local.
+      for (const {importedName: localName, localName: exportedName} of namedImports) {
+        this.addExportBinding(localName, exportedName);
+      }
+      return;
+    }
+
+    if (!this.tokens.matches1AtIndex(index, tt.string)) {
+      throw new Error("Expected string token at the end of import statement.");
+    }
+    const path = this.tokens.stringValueAtIndex(index);
+    const importInfo = this.getImportInfo(path);
+    importInfo.namedExports.push(...namedImports);
+  }
+
+   preprocessExportStarAtIndex(index) {
+    let exportedName = null;
+    if (this.tokens.matches3AtIndex(index, tt._export, tt.star, tt._as)) {
+      // export * as
+      index += 3;
+      exportedName = this.tokens.identifierNameAtIndex(index);
+      // foo from
+      index += 2;
+    } else {
+      // export * from
+      index += 3;
+    }
+    if (!this.tokens.matches1AtIndex(index, tt.string)) {
+      throw new Error("Expected string token at the end of star export statement.");
+    }
+    const path = this.tokens.stringValueAtIndex(index);
+    const importInfo = this.getImportInfo(path);
+    if (exportedName !== null) {
+      importInfo.exportStarNames.push(exportedName);
+    } else {
+      importInfo.hasStarExport = true;
+    }
+  }
+
+   getNamedImports(index) {
+    const namedImports = [];
+    while (true) {
+      if (this.tokens.matches1AtIndex(index, tt.braceR)) {
+        index++;
+        break;
+      }
+
+      const specifierInfo = getImportExportSpecifierInfo(this.tokens, index);
+      index = specifierInfo.endIndex;
+      if (!specifierInfo.isType) {
+        namedImports.push({
+          importedName: specifierInfo.leftName,
+          localName: specifierInfo.rightName,
+        });
+      }
+
+      if (this.tokens.matches2AtIndex(index, tt.comma, tt.braceR)) {
+        index += 2;
+        break;
+      } else if (this.tokens.matches1AtIndex(index, tt.braceR)) {
+        index++;
+        break;
+      } else if (this.tokens.matches1AtIndex(index, tt.comma)) {
+        index++;
+      } else {
+        throw new Error(`Unexpected token: ${JSON.stringify(this.tokens.tokens[index])}`);
+      }
+    }
+    return {newIndex: index, namedImports};
+  }
+
+  /**
+   * Get a mutable import info object for this path, creating one if it doesn't
+   * exist yet.
+   */
+   getImportInfo(path) {
+    const existingInfo = this.importInfoByPath.get(path);
+    if (existingInfo) {
+      return existingInfo;
+    }
+    const newInfo = {
+      defaultNames: [],
+      wildcardNames: [],
+      namedImports: [],
+      namedExports: [],
+      hasBareImport: false,
+      exportStarNames: [],
+      hasStarExport: false,
+    };
+    this.importInfoByPath.set(path, newInfo);
+    return newInfo;
+  }
+
+   addExportBinding(localName, exportedName) {
+    if (!this.exportBindingsByLocalName.has(localName)) {
+      this.exportBindingsByLocalName.set(localName, []);
+    }
+    this.exportBindingsByLocalName.get(localName).push(exportedName);
+  }
+
+  /**
+   * Return the code to use for the import for this path, or the empty string if
+   * the code has already been "claimed" by a previous import.
+   */
+  claimImportCode(importPath) {
+    const result = this.importsToReplace.get(importPath);
+    this.importsToReplace.set(importPath, "");
+    return result || "";
+  }
+
+  getIdentifierReplacement(identifierName) {
+    return this.identifierReplacements.get(identifierName) || null;
+  }
+
+  /**
+   * Return a string like `exports.foo = exports.bar`.
+   */
+  resolveExportBinding(assignedName) {
+    const exportedNames = this.exportBindingsByLocalName.get(assignedName);
+    if (!exportedNames || exportedNames.length === 0) {
+      return null;
+    }
+    return exportedNames.map((exportedName) => `exports.${exportedName}`).join(" = ");
+  }
+
+  /**
+   * Return all imported/exported names where we might be interested in whether usages of those
+   * names are shadowed.
+   */
+  getGlobalNames() {
+    return new Set([
+      ...this.identifierReplacements.keys(),
+      ...this.exportBindingsByLocalName.keys(),
+    ]);
+  }
+}