refactor: replace lodash with native ES2015 functions

fixes Chevrotain#1870
joliss · Oct 22, 2022 · b2d13ae · b2d13ae
1 parent 7ffce99
commit b2d13ae
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Showing 49 changed files with 805 additions and 1,085 deletions.
diff --git a/packages/chevrotain/package.json b/packages/chevrotain/package.json
@@ -76,11 +76,9 @@
     "@chevrotain/gast": "10.3.0",
     "@chevrotain/types": "10.3.0",
     "@chevrotain/utils": "10.3.0",
-    "lodash": "4.17.21",
     "regexp-to-ast": "0.5.0"
   },
   "devDependencies": {
-    "@types/lodash": "4.14.184",
     "error-stack-parser": "2.1.4",
     "esbuild": "0.15.5",
     "gen-esm-wrapper": "1.1.3",

diff --git a/packages/chevrotain/src/parse/cst/cst_visitor.ts b/packages/chevrotain/src/parse/cst/cst_visitor.ts
@@ -1,17 +1,8 @@
-import isEmpty from "lodash/isEmpty"
-import compact from "lodash/compact"
-import isArray from "lodash/isArray"
-import map from "lodash/map"
-import forEach from "lodash/forEach"
-import filter from "lodash/filter"
-import keys from "lodash/keys"
-import isFunction from "lodash/isFunction"
-import isUndefined from "lodash/isUndefined"
 import { defineNameProp } from "../../lang/lang_extensions"
 import { CstNode, ICstVisitor } from "@chevrotain/types"
 
 export function defaultVisit<IN>(ctx: any, param: IN): void {
-  const childrenNames = keys(ctx)
+  const childrenNames = Object.keys(ctx)
   const childrenNamesLength = childrenNames.length
   for (let i = 0; i < childrenNamesLength; i++) {
     const currChildName = childrenNames[i]
@@ -44,14 +35,14 @@ export function createBaseSemanticVisitorConstructor(
   const semanticProto = {
     visit: function (cstNode: CstNode | CstNode[], param: any) {
       // enables writing more concise visitor methods when CstNode has only a single child
-      if (isArray(cstNode)) {
+      if (Array.isArray(cstNode)) {
         // A CST Node's children dictionary can never have empty arrays as values
         // If a key is defined there will be at least one element in the corresponding value array.
         cstNode = cstNode[0]
       }
 
       // enables passing optional CstNodes concisely.
-      if (isUndefined(cstNode)) {
+      if (cstNode === undefined) {
         return undefined
       }
 
@@ -60,9 +51,8 @@ export function createBaseSemanticVisitorConstructor(
 
     validateVisitor: function () {
       const semanticDefinitionErrors = validateVisitor(this, ruleNames)
-      if (!isEmpty(semanticDefinitionErrors)) {
-        const errorMessages = map(
-          semanticDefinitionErrors,
+      if (semanticDefinitionErrors.length > 0) {
+        const errorMessages = semanticDefinitionErrors.map(
           (currDefError) => currDefError.msg
         )
         throw Error(
@@ -96,7 +86,7 @@ export function createBaseVisitorConstructorWithDefaults(
   defineNameProp(derivedConstructor, grammarName + "BaseSemanticsWithDefaults")
 
   const withDefaultsProto = Object.create(baseConstructor.prototype)
-  forEach(ruleNames, (ruleName) => {
+  ruleNames.forEach((ruleName) => {
     withDefaultsProto[ruleName] = defaultVisit
   })
 
@@ -130,12 +120,11 @@ export function validateMissingCstMethods(
   visitorInstance: ICstVisitor<unknown, unknown>,
   ruleNames: string[]
 ): IVisitorDefinitionError[] {
-  const missingRuleNames = filter(ruleNames, (currRuleName) => {
-    return isFunction((visitorInstance as any)[currRuleName]) === false
+  const missingRuleNames = ruleNames.filter((currRuleName) => {
+    return typeof (visitorInstance as any)[currRuleName] !== "function"
   })
 
-  const errors: IVisitorDefinitionError[] = map(
-    missingRuleNames,
+  const errors: IVisitorDefinitionError[] = missingRuleNames.map(
     (currRuleName) => {
       return {
         msg: `Missing visitor method: <${currRuleName}> on ${<any>(
@@ -147,5 +136,5 @@ export function validateMissingCstMethods(
     }
   )
 
-  return compact<IVisitorDefinitionError>(errors)
+  return errors.filter((err) => !!err)
 }
diff --git a/packages/chevrotain/src/parse/errors_public.ts b/packages/chevrotain/src/parse/errors_public.ts
@@ -1,7 +1,4 @@
 import { hasTokenLabel, tokenLabel } from "../scan/tokens_public"
-import first from "lodash/first"
-import map from "lodash/map"
-import reduce from "lodash/reduce"
 import { Alternation, NonTerminal, Rule, Terminal } from "@chevrotain/gast"
 import { getProductionDslName } from "@chevrotain/gast"
 import {
@@ -39,26 +36,23 @@ export const defaultParserErrorProvider: IParserErrorMessageProvider = {
   }): string {
     const errPrefix = "Expecting: "
     // TODO: issue: No Viable Alternative Error may have incomplete details. #502
-    const actualText = first(actual)!.image
+    const actualText = actual[0]!.image
     const errSuffix = "\nbut found: '" + actualText + "'"
 
     if (customUserDescription) {
       return errPrefix + customUserDescription + errSuffix
     } else {
-      const allLookAheadPaths = reduce(
-        expectedPathsPerAlt,
+      const allLookAheadPaths = expectedPathsPerAlt.reduce(
         (result, currAltPaths) => result.concat(currAltPaths),
         [] as TokenType[][]
       )
-      const nextValidTokenSequences = map(
-        allLookAheadPaths,
+      const nextValidTokenSequences = allLookAheadPaths.map(
         (currPath) =>
-          `[${map(currPath, (currTokenType) => tokenLabel(currTokenType)).join(
-            ", "
-          )}]`
+          `[${currPath
+            .map((currTokenType) => tokenLabel(currTokenType))
+            .join(", ")}]`
       )
-      const nextValidSequenceItems = map(
-        nextValidTokenSequences,
+      const nextValidSequenceItems = nextValidTokenSequences.map(
         (itemMsg, idx) => `  ${idx + 1}. ${itemMsg}`
       )
       const calculatedDescription = `one of these possible Token sequences:\n${nextValidSequenceItems.join(
@@ -77,18 +71,17 @@ export const defaultParserErrorProvider: IParserErrorMessageProvider = {
   }): string {
     const errPrefix = "Expecting: "
     // TODO: issue: No Viable Alternative Error may have incomplete details. #502
-    const actualText = first(actual)!.image
+    const actualText = actual[0]!.image
     const errSuffix = "\nbut found: '" + actualText + "'"
 
     if (customUserDescription) {
       return errPrefix + customUserDescription + errSuffix
     } else {
-      const nextValidTokenSequences = map(
-        expectedIterationPaths,
+      const nextValidTokenSequences = expectedIterationPaths.map(
         (currPath) =>
-          `[${map(currPath, (currTokenType) => tokenLabel(currTokenType)).join(
-            ","
-          )}]`
+          `[${currPath
+            .map((currTokenType) => tokenLabel(currTokenType))
+            .join(",")}]`
       )
       const calculatedDescription =
         `expecting at least one iteration which starts with one of these possible Token sequences::\n  ` +
@@ -137,7 +130,7 @@ export const defaultGrammarValidatorErrorProvider: IGrammarValidatorErrorMessage
       }
 
       const topLevelName = topLevelRule.name
-      const duplicateProd = first(duplicateProds)!
+      const duplicateProd = duplicateProds[0]!
       const index = duplicateProd.idx
       const dslName = getProductionDslName(duplicateProd)
       const extraArgument = getExtraProductionArgument(duplicateProd)
@@ -176,9 +169,9 @@ export const defaultGrammarValidatorErrorProvider: IGrammarValidatorErrorMessage
       ambiguityIndices: number[]
       alternation: Alternation
     }): string {
-      const pathMsg = map(options.prefixPath, (currTok) =>
-        tokenLabel(currTok)
-      ).join(", ")
+      const pathMsg = options.prefixPath
+        .map((currTok) => tokenLabel(currTok))
+        .join(", ")
       const occurrence =
         options.alternation.idx === 0 ? "" : options.alternation.idx
       const errMsg =
@@ -199,9 +192,9 @@ export const defaultGrammarValidatorErrorProvider: IGrammarValidatorErrorMessage
       ambiguityIndices: number[]
       alternation: Alternation
     }): string {
-      const pathMsg = map(options.prefixPath, (currtok) =>
-        tokenLabel(currtok)
-      ).join(", ")
+      const pathMsg = options.prefixPath
+        .map((currtok) => tokenLabel(currtok))
+        .join(", ")
       const occurrence =
         options.alternation.idx === 0 ? "" : options.alternation.idx
       let currMessage =
@@ -277,8 +270,7 @@ export const defaultGrammarValidatorErrorProvider: IGrammarValidatorErrorMessage
       leftRecursionPath: Rule[]
     }): string {
       const ruleName = options.topLevelRule.name
-      const pathNames = map(
-        options.leftRecursionPath,
+      const pathNames = options.leftRecursionPath.map(
         (currRule) => currRule.name
       )
       const leftRecursivePath = `${ruleName} --> ${pathNames

diff --git a/packages/chevrotain/src/parse/exceptions_public.ts b/packages/chevrotain/src/parse/exceptions_public.ts
@@ -1,4 +1,3 @@
-import includes from "lodash/includes"
 import {
   IToken,
   IRecognitionException,
@@ -22,7 +21,7 @@ Object.freeze(RECOGNITION_EXCEPTION_NAMES)
 // hacks to bypass no support for custom Errors in javascript/typescript
 export function isRecognitionException(error: Error) {
   // can't do instanceof on hacked custom js exceptions
-  return includes(RECOGNITION_EXCEPTION_NAMES, error.name)
+  return RECOGNITION_EXCEPTION_NAMES.indexOf(error.name) !== -1
 }
 
 abstract class RecognitionException