refactor: deduplicate isBooleanLiteral & getFirstMatcherArg utils

Author: G-Rath

src/rules/prefer-comparison-matcher.ts

@@ -1,29 +1,14 @@
 import { AST_NODE_TYPES, TSESTree } from '@typescript-eslint/utils';
 import {
   EqualityMatcher,
-  ParsedExpectFnCall,
   createRule,
-  followTypeAssertionChain,
   getAccessorValue,
+  getFirstMatcherArg,
+  isBooleanLiteral,
   isStringNode,
   parseJestFnCall,
 } from './utils';
 
-const isBooleanLiteral = (
-  node: TSESTree.Node,
-): node is TSESTree.BooleanLiteral =>
-  node.type === AST_NODE_TYPES.Literal && typeof node.value === 'boolean';
-
-const getFirstMatcherArg = (expectFnCall: ParsedExpectFnCall) => {
-  const [firstArg] = expectFnCall.args;
-
-  if (firstArg.type === AST_NODE_TYPES.SpreadElement) {
-    return firstArg;
-  }
-
-  return followTypeAssertionChain(firstArg);
-};
-
 const isString = (node: TSESTree.Node) => {
   return isStringNode(node) || node.type === AST_NODE_TYPES.TemplateLiteral;
 };

src/rules/prefer-equality-matcher.ts

@@ -1,29 +1,14 @@
-import { AST_NODE_TYPES, TSESLint, TSESTree } from '@typescript-eslint/utils';
+import { AST_NODE_TYPES, TSESLint } from '@typescript-eslint/utils';
 import {
   EqualityMatcher,
   ModifierName,
-  ParsedExpectFnCall,
   createRule,
-  followTypeAssertionChain,
   getAccessorValue,
+  getFirstMatcherArg,
+  isBooleanLiteral,
   parseJestFnCall,
 } from './utils';
 
-const isBooleanLiteral = (
-  node: TSESTree.Node,
-): node is TSESTree.BooleanLiteral =>
-  node.type === AST_NODE_TYPES.Literal && typeof node.value === 'boolean';
-
-const getFirstMatcherArg = (expectFnCall: ParsedExpectFnCall) => {
-  const [firstArg] = expectFnCall.args;
-
-  if (firstArg.type === AST_NODE_TYPES.SpreadElement) {
-    return firstArg;
-  }
-
-  return followTypeAssertionChain(firstArg);
-};
-
 export default createRule({
   name: __filename,
   meta: {

src/rules/prefer-to-be.ts

@@ -4,8 +4,8 @@ import {
   EqualityMatcher,
   ParsedExpectFnCall,
   createRule,
-  followTypeAssertionChain,
   getAccessorValue,
+  getFirstMatcherArg,
   isIdentifier,
   parseJestFnCall,
   replaceAccessorFixer,
@@ -38,16 +38,6 @@ const shouldUseToBe = (expectFnCall: ParsedExpectFnCall): boolean => {
   return firstArg.type === AST_NODE_TYPES.TemplateLiteral;
 };
 
-const getFirstMatcherArg = (expectFnCall: ParsedExpectFnCall) => {
-  const [firstArg] = expectFnCall.args;
-
-  if (firstArg.type === AST_NODE_TYPES.SpreadElement) {
-    return firstArg;
-  }
-
-  return followTypeAssertionChain(firstArg);
-};
-
 type MessageId =
   | 'useToBe'
   | 'useToBeUndefined'

src/rules/prefer-to-contain.ts

@@ -4,30 +4,15 @@ import {
   EqualityMatcher,
   KnownCallExpression,
   ModifierName,
-  ParsedExpectFnCall,
   createRule,
-  followTypeAssertionChain,
   getAccessorValue,
+  getFirstMatcherArg,
   hasOnlyOneArgument,
+  isBooleanLiteral,
   isSupportedAccessor,
   parseJestFnCall,
 } from './utils';
 
-const isBooleanLiteral = (
-  node: TSESTree.Node,
-): node is TSESTree.BooleanLiteral =>
-  node.type === AST_NODE_TYPES.Literal && typeof node.value === 'boolean';
-
-const getFirstMatcherArg = (expectFnCall: ParsedExpectFnCall) => {
-  const [firstArg] = expectFnCall.args;
-
-  if (firstArg.type === AST_NODE_TYPES.SpreadElement) {
-    return firstArg;
-  }
-
-  return followTypeAssertionChain(firstArg);
-};
-
 type FixableIncludesCallExpression = KnownCallExpression<'includes'> &
   CallExpressionWithSingleArgument;
 

src/rules/utils/misc.ts

@@ -11,7 +11,8 @@ import {
   getAccessorValue,
   isSupportedAccessor,
 } from './accessors';
-import { isTypeOfJestFnCall } from './parseJestFnCall';
+import { followTypeAssertionChain } from './followTypeAssertionChain';
+import { ParsedExpectFnCall, isTypeOfJestFnCall } from './parseJestFnCall';
 
 const REPO_URL = 'https://github.com/jest-community/eslint-plugin-jest';
 
@@ -191,3 +192,20 @@ export const findTopMostCallExpression = (
 
   return topMostCallExpression;
 };
+
+export const isBooleanLiteral = (
+  node: TSESTree.Node,
+): node is TSESTree.BooleanLiteral =>
+  node.type === AST_NODE_TYPES.Literal && typeof node.value === 'boolean';
+
+export const getFirstMatcherArg = (
+  expectFnCall: ParsedExpectFnCall,
+): TSESTree.SpreadElement | TSESTree.Expression => {
+  const [firstArg] = expectFnCall.args;
+
+  if (firstArg.type === AST_NODE_TYPES.SpreadElement) {
+    return firstArg;
+  }
+
+  return followTypeAssertionChain(firstArg);
+};