Aug 19, 2024 · Mar 14, 2024 · Mar 27, 2024 · Apr 10, 2024 · May 12, 2024 · May 12, 2024
diff --git a/packages/eslint-plugin/src/rules/no-unnecessary-template-expression.ts b/packages/eslint-plugin/src/rules/no-unnecessary-template-expression.ts
 import {
  createRule,
  getConstrainedTypeAtLocation,
  getMovedNodeCode,
  getParserServices,
  isTypeFlagSet,
  isUndefinedIdentifier,
          context.report({
            node: node.expressions[0],
            messageId: 'noUnnecessaryTemplateExpression',
            fix(fixer): TSESLint.RuleFix[] {
              const [prevQuasi, nextQuasi] = node.quasis;

              // Remove the quasis and backticks.
              return [
                fixer.removeRange([
                  prevQuasi.range[1] - 3,
                  node.expressions[0].range[0],
                ]),

                fixer.removeRange([
                  node.expressions[0].range[1],
                  nextQuasi.range[0] + 2,
                ]),
              ];
            fix(fixer): TSESLint.RuleFix | null {
              const wrappingCode = getMovedNodeCode({
                sourceCode: context.sourceCode,
                nodeToMove: node.expressions[0],
                destinationNode: node,
              });

              return fixer.replaceText(node, wrappingCode);
            },
          });

diff --git a/packages/eslint-plugin/src/util/getWrappingFixer.ts b/packages/eslint-plugin/src/util/getWrappingFixer.ts
    return fixer.replaceText(node, code);
  };
 }
 /**
 * If the node to be moved and the destination node require parentheses, include parentheses in the node to be moved.
 * @param sourceCode Source code of current file
 * @param nodeToMove Nodes that need to be moved
 * @param destinationNode Final destination node with nodeToMove
 * @returns If parentheses are required, code for the nodeToMove node is returned with parentheses at both ends of the code.
 */
 export function getMovedNodeCode(params: {
  sourceCode: Readonly<TSESLint.SourceCode>;
  nodeToMove: TSESTree.Node;
  destinationNode: TSESTree.Node;
 }): string {
  const { sourceCode, nodeToMove: existingNode, destinationNode } = params;
  const code = sourceCode.getText(existingNode);
  if (isStrongPrecedenceNode(existingNode)) {
    // Moved node never needs parens
    return code;
  }

  if (!isWeakPrecedenceParent(destinationNode)) {
    // Destination would never needs parens, regardless what node moves there
    return code;
  }

  // Parens may be necessary
  return `(${code})`;
 }

 /**
 * Check if a node will always have the same precedence if it's parent changes.
 * Check if a node's parent could have different precedence if the node changes.
 */
 function isWeakPrecedenceParent(node: TSESTree.Node): boolean {
  // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
  const parent = node.parent!;
  const parent = node.parent;
  if (!parent) {
    return false;
  }

  if (
    parent.type === AST_NODE_TYPES.UpdateExpression ||
diff --git a/packages/eslint-plugin/tests/rules/no-unnecessary-template-expression.test.ts b/packages/eslint-plugin/tests/rules/no-unnecessary-template-expression.test.ts
        },
      ],
    },
    {
      code: "true ? `${'test' || ''}`.trim() : undefined;",
      output: "true ? ('test' || '').trim() : undefined;",
      errors: [
        {
          messageId: 'noUnnecessaryTemplateExpression',
        },
      ],
    },
  ],
 });
Original file line number	Diff line number	Diff line change
Expand Up		@@ -5,6 +5,7 @@ import * as ts from 'typescript';
		import {
		createRule,
		getConstrainedTypeAtLocation,
		getMovedNodeCode,
		getParserServices,
		isTypeFlagSet,
		isUndefinedIdentifier,
Expand DownExpand Up		@@ -106,21 +107,14 @@ export default createRule<[], MessageId>({
		context.report({
		node: node.expressions[0],
		messageId: 'noUnnecessaryTemplateExpression',
		fix(fixer): TSESLint.RuleFix[] {
		const [prevQuasi, nextQuasi] = node.quasis;

		// Remove the quasis and backticks.
		return [
		fixer.removeRange([
		prevQuasi.range[1] - 3,
		node.expressions[0].range[0],
		]),

		fixer.removeRange([
		node.expressions[0].range[1],
		nextQuasi.range[0] + 2,
		]),
		];
		fix(fixer): TSESLint.RuleFix \| null {
		const wrappingCode = getMovedNodeCode({
		sourceCode: context.sourceCode,
		nodeToMove: node.expressions[0],
		destinationNode: node,
		});

		return fixer.replaceText(node, wrappingCode);
		},
		});

Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -74,6 +74,33 @@
		return fixer.replaceText(node, code);
		};
		}
		/**
		* If the node to be moved and the destination node require parentheses, include parentheses in the node to be moved.
		* @param sourceCode Source code of current file
		* @param nodeToMove Nodes that need to be moved
		* @param destinationNode Final destination node with nodeToMove
		* @returns If parentheses are required, code for the nodeToMove node is returned with parentheses at both ends of the code.
		*/
		export function getMovedNodeCode(params: {
		sourceCode: Readonly<TSESLint.SourceCode>;
		nodeToMove: TSESTree.Node;
		destinationNode: TSESTree.Node;
		}): string {
		const { sourceCode, nodeToMove: existingNode, destinationNode } = params;
		const code = sourceCode.getText(existingNode);
		if (isStrongPrecedenceNode(existingNode)) {
		// Moved node never needs parens
		return code;
		}

		if (!isWeakPrecedenceParent(destinationNode)) {
Copy link Member JoshuaKGoldbergAug 19, 2024 Choose a reason for hiding this comment The reason will be displayed to describe this comment to others.Learn more. [Praise] Great reuse of the existing functions!
		// Destination would never needs parens, regardless what node moves there
		return code;
		}

		// Parens may be necessary
		return `(${code})`;
		}

		/**
		* Check if a node will always have the same precedence if it's parent changes.
Expand All		@@ -98,8 +125,10 @@
		* Check if a node's parent could have different precedence if the node changes.
		*/
		function isWeakPrecedenceParent(node: TSESTree.Node): boolean {
		// eslint-disable-next-line @typescript-eslint/no-non-null-assertion
		const parent = node.parent!;
		const parent = node.parent;
		if (!parent) {
		return false;
Check warning on line 130 in packages/eslint-plugin/src/util/getWrappingFixer.ts View check run for this annotation Codecov/ codecov/patch packages/eslint-plugin/src/util/getWrappingFixer.ts#L130 `Added line #L130 was not covered by tests`
		}

		if (
		parent.type === AST_NODE_TYPES.UpdateExpression \|\|
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -1127,5 +1127,14 @@ declare const nested: string, interpolation: string;
		},
		],
		},
		{
		code: "true ? `${'test' \|\| ''}`.trim() : undefined;",
		output: "true ? ('test' \|\| '').trim() : undefined;",
		errors: [
		{
		messageId: 'noUnnecessaryTemplateExpression',
		},
		],
		},
		],
		});