From b17387c34d86c353434e40aa748bb5182033cfd6 Mon Sep 17 00:00:00 2001
From: Philipp Burckhardt <pburckhardt@outlook.com>
Date: Sat, 22 Aug 2026 01:13:39 -0500
Subject: [PATCH 1/6] feat: add `no-unnecessary-format` ESLint rule

Adds a custom ESLint rule which disallows calls to the format function
exported by `@stdlib/string/format` when the format string does not
contain any placeholders. Such calls are unnecessary, as the format
function simply returns the input string unchanged. The rule is
auto-fixable: the fixer replaces the format call with the string
literal argument.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

---
type: pre_commit_static_analysis_report
description: Results of running static analysis checks when committing changes.
report:
  - task: lint_filenames
    status: passed
  - task: lint_editorconfig
    status: passed
  - task: lint_markdown_pkg_readmes
    status: na
  - task: lint_markdown_docs
    status: na
  - task: lint_markdown
    status: na
  - task: lint_package_json
    status: na
  - task: lint_repl_help
    status: na
  - task: lint_javascript_src
    status: na
  - task: lint_javascript_cli
    status: na
  - task: lint_javascript_examples
    status: na
  - task: lint_javascript_tests
    status: na
  - task: lint_javascript_benchmarks
    status: na
  - task: lint_python
    status: na
  - task: lint_r
    status: na
  - task: lint_c_src
    status: na
  - task: lint_c_examples
    status: na
  - task: lint_c_benchmarks
    status: na
  - task: lint_c_tests_fixtures
    status: na
  - task: lint_shell
    status: na
  - task: lint_typescript_declarations
    status: passed
  - task: lint_typescript_tests
    status: na
  - task: lint_license_headers
    status: passed
---
---
 etc/eslint/rules/stdlib.js                    |  22 +-
 .../@stdlib/_tools/eslint/rules/lib/index.js  |   9 +
 .../rules/no-unnecessary-format/README.md     | 136 +++++++++++++
 .../no-unnecessary-format/examples/index.js   |  52 +++++
 .../rules/no-unnecessary-format/lib/index.js  |  39 ++++
 .../rules/no-unnecessary-format/lib/main.js   | 191 ++++++++++++++++++
 .../rules/no-unnecessary-format/package.json  |  66 ++++++
 .../test/fixtures/invalid.js                  | 147 ++++++++++++++
 .../test/fixtures/unvalidated.js              |  57 ++++++
 .../test/fixtures/valid.js                    | 119 +++++++++++
 .../rules/no-unnecessary-format/test/test.js  |  98 +++++++++
 11 files changed, 935 insertions(+), 1 deletion(-)
 create mode 100644 lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/README.md
 create mode 100644 lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/examples/index.js
 create mode 100644 lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/lib/index.js
 create mode 100644 lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/lib/main.js
 create mode 100644 lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/package.json
 create mode 100644 lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/invalid.js
 create mode 100644 lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/unvalidated.js
 create mode 100644 lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/valid.js
 create mode 100644 lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/test.js

diff --git a/etc/eslint/rules/stdlib.js b/etc/eslint/rules/stdlib.js
index 1c84b79de46c..cf117b2c65b6 100644
--- a/etc/eslint/rules/stdlib.js
+++ b/etc/eslint/rules/stdlib.js
@@ -1,4 +1,4 @@
-/* eslint-disable stdlib/jsdoc-doctest-marker, stdlib/jsdoc-doctest, stdlib/jsdoc-example-require-spacing, stdlib/jsdoc-no-tabs */
+/* eslint-disable stdlib/jsdoc-doctest-marker, stdlib/jsdoc-example-require-spacing, stdlib/jsdoc-no-tabs */
 
 /**
 * @license Apache-2.0
@@ -4442,6 +4442,26 @@ rules[ 'stdlib/no-nested-require' ] = 'error';
 */
 rules[ 'stdlib/no-unnecessary-nested-functions' ] = 'error';
 
+/**
+* Disallow format calls that do not perform string interpolation.
+*
+* @name no-unnecessary-format
+* @memberof rules
+* @type {string}
+* @default 'error'
+*
+* @example
+* // Bad...
+* var format = require( '@stdlib/string/format' );
+*
+* throw new Error( format( 'invalid argument.' ) );
+*
+* @example
+* // Good...
+* throw new Error( 'invalid argument.' );
+*/
+rules[ 'stdlib/no-unnecessary-format' ] = 'error';
+
 /**
 * Disallow the use of the `new Array()` constructor.
 *
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/lib/index.js b/lib/node_modules/@stdlib/_tools/eslint/rules/lib/index.js
index c90cab4a4289..25ac65d000ac 100644
--- a/lib/node_modules/@stdlib/_tools/eslint/rules/lib/index.js
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/lib/index.js
@@ -1017,6 +1017,15 @@ setReadOnly( rules, 'no-single-property-require', require( '@stdlib/_tools/eslin
 */
 setReadOnly( rules, 'no-unassigned-require', require( '@stdlib/_tools/eslint/rules/no-unassigned-require' ) );
 
+/**
+* @name no-unnecessary-format
+* @memberof rules
+* @readonly
+* @type {Function}
+* @see {@link module:@stdlib/_tools/eslint/rules/no-unnecessary-format}
+*/
+setReadOnly( rules, 'no-unnecessary-format', require( '@stdlib/_tools/eslint/rules/no-unnecessary-format' ) );
+
 /**
 * @name no-unnecessary-nested-functions
 * @memberof rules
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/README.md b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/README.md
new file mode 100644
index 000000000000..0de4bc96bbd7
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/README.md
@@ -0,0 +1,136 @@
+<!--
+
+@license Apache-2.0
+
+Copyright (c) 2026 The Stdlib Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+-->
+
+# no-unnecessary-format
+
+> [ESLint rule][eslint-rules] disallowing format calls that do not perform string interpolation.
+
+<section class="intro">
+
+</section>
+
+<!-- /.intro -->
+
+<section class="usage">
+
+## Usage
+
+```javascript
+var rule = require( '@stdlib/_tools/eslint/rules/no-unnecessary-format' );
+```
+
+#### rule
+
+[ESLint rule][eslint-rules] disallowing calls to the format function exported by [`@stdlib/string/format`][@stdlib/string/format] when the format string does not contain any placeholders. Such calls are unnecessary, as the format function simply returns the input string unchanged.
+
+**Bad**:
+
+<!-- run-disable -->
+
+<!-- eslint-disable stdlib/no-unnecessary-format -->
+
+```javascript
+var format = require( '@stdlib/string/format' );
+
+throw new Error( format( 'invalid argument.' ) );
+```
+
+**Good**:
+
+<!-- run-disable -->
+
+```javascript
+throw new Error( 'invalid argument.' );
+```
+
+</section>
+
+<!-- /.usage -->
+
+<section class="notes">
+
+</section>
+
+<!-- /.notes -->
+
+<section class="examples">
+
+## Examples
+
+<!-- eslint no-undef: "error" -->
+
+```javascript
+var Linter = require( 'eslint' ).Linter;
+var rule = require( '@stdlib/_tools/eslint/rules/no-unnecessary-format' );
+
+var linter = new Linter();
+
+var code = [
+    'var format = require( \'@stdlib/string/format\' );',
+    '',
+    'throw new Error( format( \'invalid argument.\' ) );'
+].join( '\n' );
+
+linter.defineRule( 'no-unnecessary-format', rule );
+
+var result = linter.verify( code, {
+    'rules': {
+        'no-unnecessary-format': 'error'
+    }
+});
+/* returns
+    [
+        {
+            'ruleId': 'no-unnecessary-format',
+            'severity': 2,
+            'message': 'Unnecessary format call. No placeholders found in format string.',
+            'line': 3,
+            'column': 18,
+            'nodeType': 'CallExpression',
+            'endLine': 3,
+            'endColumn': 47
+        }
+    ]
+*/
+```
+
+</section>
+
+<!-- /.examples -->
+
+<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->
+
+<section class="related">
+
+</section>
+
+<!-- /.related -->
+
+<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="links">
+
+[eslint-rules]: https://eslint.org/docs/developer-guide/working-with-rules
+
+[@stdlib/string/format]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/string/format
+
+</section>
+
+<!-- /.links -->
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/examples/index.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/examples/index.js
new file mode 100644
index 000000000000..05b7adce2e11
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/examples/index.js
@@ -0,0 +1,52 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+var Linter = require( 'eslint' ).Linter;
+var rule = require( './../lib' );
+
+var linter = new Linter();
+var code = [
+	'var format = require( \'@stdlib/string/format\' );',
+	'',
+	'throw new Error( format( \'invalid argument.\' ) );'
+].join( '\n' );
+
+linter.defineRule( 'no-unnecessary-format', rule );
+
+var results = linter.verify( code, {
+	'rules': {
+		'no-unnecessary-format': 'error'
+	}
+});
+console.log( results );
+/* =>
+	[
+		{
+			'ruleId': 'no-unnecessary-format',
+			'severity': 2,
+			'message': 'Unnecessary format call. No placeholders found in format string.',
+			'line': 3,
+			'column': 18,
+			'nodeType': 'CallExpression',
+			'endLine': 3,
+			'endColumn': 47
+		}
+	]
+*/
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/lib/index.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/lib/index.js
new file mode 100644
index 000000000000..83700c0f6778
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/lib/index.js
@@ -0,0 +1,39 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+/**
+* ESLint rule disallowing format calls that do not perform string interpolation.
+*
+* @module @stdlib/_tools/eslint/rules/no-unnecessary-format
+*
+* @example
+* var rule = require( '@stdlib/_tools/eslint/rules/no-unnecessary-format' );
+*
+* console.log( rule );
+*/
+
+// MODULES //
+
+var main = require( './main.js' );
+
+
+// EXPORTS //
+
+module.exports = main;
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/lib/main.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/lib/main.js
new file mode 100644
index 000000000000..3954c479df12
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/lib/main.js
@@ -0,0 +1,191 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var formatTokenize = require( '@stdlib/string/base/format-tokenize' );
+
+
+// VARIABLES //
+
+var PKG = '@stdlib/string/format';
+var rule;
+
+
+// FUNCTIONS //
+
+/**
+* Returns a boolean indicating whether a provided identifier name resolves to the format function exported by `@stdlib/string/format`.
+*
+* ## Notes
+*
+* -   The function walks parent scopes and inspects the **nearest** binding for the provided name, thus guarding against shadowed symbols.
+*
+* @private
+* @param {Object} scope - scope
+* @param {string} name - identifier name
+* @returns {boolean} boolean indicating whether an identifier name resolves to the format function
+*/
+function isFormat( scope, name ) {
+	var v;
+
+	while ( scope ) {
+		if ( scope.set.has( name ) ) {
+			v = scope.set.get( name );
+			if (
+				v.defs.length > 0 &&
+				v.defs[ 0 ].node.type === 'VariableDeclarator' &&
+				v.defs[ 0 ].node.init &&
+				v.defs[ 0 ].node.init.type === 'CallExpression' &&
+				v.defs[ 0 ].node.init.callee.name === 'require' &&
+				v.defs[ 0 ].node.init.arguments.length > 0 &&
+				v.defs[ 0 ].node.init.arguments[ 0 ].value === PKG
+			) {
+				return true;
+			}
+			return false;
+		}
+		scope = scope.upper;
+	}
+	return false;
+}
+
+/**
+* Returns a boolean indicating whether a format string contains any placeholders.
+*
+* @private
+* @param {string} str - format string
+* @returns {boolean} boolean indicating whether a format string contains placeholders
+*/
+function hasPlaceholders( str ) {
+	var tokens;
+	var i;
+
+	tokens = formatTokenize( str );
+	for ( i = 0; i < tokens.length; i++ ) {
+		if ( typeof tokens[ i ] !== 'string' ) {
+			return true;
+		}
+	}
+	return false;
+}
+
+/**
+* Returns a boolean indicating whether a format call can be safely auto-fixed.
+*
+* ## Notes
+*
+* -   Auto-fixing is unsafe when the format string contains `%%` escape sequences, as `format` converts `%%` to `%` at runtime, so replacing the call with the raw string literal would change the program's behavior.
+* -   Auto-fixing is also unsafe when extra arguments are provided beyond the format string, as those expressions may have side effects.
+*
+* @private
+* @param {ASTNode} node - call expression node
+* @param {string} str - format string value
+* @returns {boolean} boolean indicating whether the call can be auto-fixed
+*/
+function canAutofix( node, str ) {
+	if ( node.arguments.length > 1 ) {
+		return false;
+	}
+	if ( str.indexOf( '%%' ) !== -1 ) {
+		return false;
+	}
+	return true;
+}
+
+/**
+* Rule for disallowing format calls that do not perform string interpolation.
+*
+* @param {Object} context - ESLint context
+* @returns {Object} validators
+*/
+function main( context ) {
+	var source = context.sourceCode;
+
+	/**
+	* Validates a call expression.
+	*
+	* @private
+	* @param {ASTNode} node - node to examine
+	*/
+	function validate( node ) {
+		var str;
+
+		// Note: member expression callees (e.g., `format.call( ... )` and `format.apply( ... )`) are intentionally skipped, as the callee is not an `Identifier` node...
+		if (
+			node.callee === void 0 ||
+			node.callee.type !== 'Identifier' ||
+			!isFormat( source.getScope( node ), node.callee.name )
+		) {
+			return;
+		}
+		// Only check calls in which the format string is a string literal...
+		if (
+			node.arguments.length === 0 ||
+			node.arguments[ 0 ].type !== 'Literal' ||
+			typeof node.arguments[ 0 ].value !== 'string'
+		) {
+			return;
+		}
+		str = node.arguments[ 0 ].value;
+		if ( !hasPlaceholders( str ) ) {
+			context.report({
+				'node': node,
+				'message': 'Unnecessary format call. No placeholders found in format string.',
+				'fix': ( canAutofix( node, str ) ) ? fix : null
+			});
+		}
+
+		/**
+		* Fixes the lint error by replacing the format call with the string literal.
+		*
+		* @private
+		* @param {Object} fixer - ESLint fixer
+		* @returns {Object} fix object
+		*/
+		function fix( fixer ) {
+			return fixer.replaceText( node, source.getText( node.arguments[ 0 ] ) );
+		}
+	}
+
+	return {
+		'CallExpression': validate
+	};
+}
+
+
+// MAIN //
+
+rule = {
+	'meta': {
+		'type': 'suggestion',
+		'docs': {
+			'description': 'disallow format calls that do not perform string interpolation'
+		},
+		'fixable': 'code',
+		'schema': []
+	},
+	'create': main
+};
+
+
+// EXPORTS //
+
+module.exports = rule;
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/package.json b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/package.json
new file mode 100644
index 000000000000..073e6ab66dca
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/package.json
@@ -0,0 +1,66 @@
+{
+  "name": "@stdlib/_tools/eslint/rules/no-unnecessary-format",
+  "version": "0.0.0",
+  "description": "ESLint rule disallowing format calls that do not perform string interpolation.",
+  "license": "Apache-2.0",
+  "author": {
+    "name": "The Stdlib Authors",
+    "url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
+  },
+  "contributors": [
+    {
+      "name": "The Stdlib Authors",
+      "url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
+    }
+  ],
+  "bin": {},
+  "main": "./lib",
+  "directories": {
+    "example": "./examples",
+    "lib": "./lib",
+    "test": "./test"
+  },
+  "scripts": {},
+  "homepage": "https://github.com/stdlib-js/stdlib",
+  "repository": {
+    "type": "git",
+    "url": "git://github.com/stdlib-js/stdlib.git"
+  },
+  "bugs": {
+    "url": "https://github.com/stdlib-js/stdlib/issues"
+  },
+  "dependencies": {},
+  "devDependencies": {},
+  "engines": {
+    "node": ">=0.10.0",
+    "npm": ">2.7.0"
+  },
+  "os": [
+    "aix",
+    "darwin",
+    "freebsd",
+    "linux",
+    "macos",
+    "openbsd",
+    "sunos",
+    "win32",
+    "windows"
+  ],
+  "keywords": [
+    "stdlib",
+    "tools",
+    "tool",
+    "eslint",
+    "lint",
+    "custom",
+    "rules",
+    "rule",
+    "plugin",
+    "format",
+    "interpolate",
+    "string",
+    "useless",
+    "unnecessary",
+    "placeholders"
+  ]
+}
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/invalid.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/invalid.js
new file mode 100644
index 000000000000..203045515d54
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/invalid.js
@@ -0,0 +1,147 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+var invalid = [];
+var test;
+
+// Static string...
+test = {
+	'code': [
+		'var format = require( \'@stdlib/string/format\' );',
+		'',
+		'var str = format( \'hello world\' );'
+	].join( '\n' ),
+	'output': [
+		'var format = require( \'@stdlib/string/format\' );',
+		'',
+		'var str = \'hello world\';'
+	].join( '\n' ),
+	'errors': [
+		{
+			'message': 'Unnecessary format call. No placeholders found in format string.',
+			'type': 'CallExpression'
+		}
+	]
+};
+invalid.push( test );
+
+// Nested in `new Error`...
+test = {
+	'code': [
+		'var format = require( \'@stdlib/string/format\' );',
+		'',
+		'throw new Error( format( \'invalid argument.\' ) );'
+	].join( '\n' ),
+	'output': [
+		'var format = require( \'@stdlib/string/format\' );',
+		'',
+		'throw new Error( \'invalid argument.\' );'
+	].join( '\n' ),
+	'errors': [
+		{
+			'message': 'Unnecessary format call. No placeholders found in format string.',
+			'type': 'CallExpression'
+		}
+	]
+};
+invalid.push( test );
+
+// Escaped percent only (no conversion; no autofix due to `%%` unescaping)...
+test = {
+	'code': [
+		'var format = require( \'@stdlib/string/format\' );',
+		'',
+		'var str = format( \'100%%\' );'
+	].join( '\n' ),
+	'errors': [
+		{
+			'message': 'Unnecessary format call. No placeholders found in format string.',
+			'type': 'CallExpression'
+		}
+	]
+};
+invalid.push( test );
+
+// Extra arguments (no autofix to avoid dropping expressions with side effects)...
+test = {
+	'code': [
+		'var format = require( \'@stdlib/string/format\' );',
+		'',
+		'var str = format( \'hello\', x );'
+	].join( '\n' ),
+	'errors': [
+		{
+			'message': 'Unnecessary format call. No placeholders found in format string.',
+			'type': 'CallExpression'
+		}
+	]
+};
+invalid.push( test );
+
+// Alias other than `format`...
+test = {
+	'code': [
+		'var fmt = require( \'@stdlib/string/format\' );',
+		'',
+		'var str = fmt( \'static text\' );'
+	].join( '\n' ),
+	'output': [
+		'var fmt = require( \'@stdlib/string/format\' );',
+		'',
+		'var str = \'static text\';'
+	].join( '\n' ),
+	'errors': [
+		{
+			'message': 'Unnecessary format call. No placeholders found in format string.',
+			'type': 'CallExpression'
+		}
+	]
+};
+invalid.push( test );
+
+// Inner scope resolving to outer require...
+test = {
+	'code': [
+		'var format = require( \'@stdlib/string/format\' );',
+		'',
+		'function foo() {',
+		'  return format( \'static text\' );',
+		'}'
+	].join( '\n' ),
+	'output': [
+		'var format = require( \'@stdlib/string/format\' );',
+		'',
+		'function foo() {',
+		'  return \'static text\';',
+		'}'
+	].join( '\n' ),
+	'errors': [
+		{
+			'message': 'Unnecessary format call. No placeholders found in format string.',
+			'type': 'CallExpression'
+		}
+	]
+};
+invalid.push( test );
+
+
+// EXPORTS //
+
+module.exports = invalid;
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/unvalidated.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/unvalidated.js
new file mode 100644
index 000000000000..e39c20a21b43
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/unvalidated.js
@@ -0,0 +1,57 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+var unvalidated = [];
+var test;
+
+test = {
+	'code': [
+		'var x = 123;'
+	].join( '\n' )
+};
+unvalidated.push( test );
+
+test = {
+	'code': [
+		'var str = format( \'hello\' );'
+	].join( '\n' )
+};
+unvalidated.push( test );
+
+test = {
+	'code': [
+		'var format = require( \'@stdlib/string/format\' );'
+	].join( '\n' )
+};
+unvalidated.push( test );
+
+test = {
+	'code': [
+		'var format = require( \'@stdlib/string/format\' );',
+		'',
+		'var str = format();'
+	].join( '\n' )
+};
+unvalidated.push( test );
+
+
+// EXPORTS //
+
+module.exports = unvalidated;
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/valid.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/valid.js
new file mode 100644
index 000000000000..7f25c605455a
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/valid.js
@@ -0,0 +1,119 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+var valid = [];
+var test;
+
+// Format string with a placeholder...
+test = {
+	'code': [
+		'var format = require( \'@stdlib/string/format\' );',
+		'',
+		'var str = format( \'%s\', \'foo\' );'
+	].join( '\n' )
+};
+valid.push( test );
+
+test = {
+	'code': [
+		'var format = require( \'@stdlib/string/format\' );',
+		'',
+		'throw new Error( format( \'invalid argument. Must provide a string. Value: `%s`.\', \'foo\' ) );'
+	].join( '\n' )
+};
+valid.push( test );
+
+// Escaped percent sign with a placeholder...
+test = {
+	'code': [
+		'var format = require( \'@stdlib/string/format\' );',
+		'',
+		'var str = format( \'%d%%\', 10 );'
+	].join( '\n' )
+};
+valid.push( test );
+
+// Non-literal format string...
+test = {
+	'code': [
+		'var format = require( \'@stdlib/string/format\' );',
+		'',
+		'var str = \'hello\';',
+		'var out = format( str );'
+	].join( '\n' )
+};
+valid.push( test );
+
+// Calls via `#.call` and `#.apply`...
+test = {
+	'code': [
+		'var format = require( \'@stdlib/string/format\' );',
+		'',
+		'var str = format.call( null, \'hello\' );'
+	].join( '\n' )
+};
+valid.push( test );
+
+test = {
+	'code': [
+		'var format = require( \'@stdlib/string/format\' );',
+		'',
+		'var str = format.apply( null, [ \'hello\' ] );'
+	].join( '\n' )
+};
+valid.push( test );
+
+// Shadowed symbols...
+test = {
+	'code': [
+		'var format = require( \'@stdlib/string/format\' );',
+		'',
+		'function foo( format ) {',
+		'  return format( \'hello\' );',
+		'}'
+	].join( '\n' )
+};
+valid.push( test );
+
+// Unrelated symbols...
+test = {
+	'code': [
+		'var format = require( \'d3-format\' );',
+		'',
+		'var str = format( \'hello\' );'
+	].join( '\n' )
+};
+valid.push( test );
+
+test = {
+	'code': [
+		'function format( str ) {',
+		'  return str;',
+		'}',
+		'',
+		'var str = format( \'hello\' );'
+	].join( '\n' )
+};
+valid.push( test );
+
+
+// EXPORTS //
+
+module.exports = valid;
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/test.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/test.js
new file mode 100644
index 000000000000..b77dcc36d61d
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/test.js
@@ -0,0 +1,98 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var tape = require( 'tape' );
+var RuleTester = require( 'eslint' ).RuleTester;
+var rule = require( './../lib' );
+
+
+// FIXTURES //
+
+var valid = require( './fixtures/valid.js' );
+var invalid = require( './fixtures/invalid.js' );
+var unvalidated = require( './fixtures/unvalidated.js' );
+
+
+// TESTS //
+
+tape( 'main export is an object', function test( t ) {
+	t.ok( true, __filename );
+	t.strictEqual( typeof rule, 'object', 'main export is an object' );
+	t.end();
+});
+
+tape( 'the function positively validates format calls which perform string interpolation', function test( t ) {
+	var tester = new RuleTester({
+		'parserOptions': {
+			'ecmaVersion': 2020
+		}
+	});
+
+	try {
+		tester.run( 'no-unnecessary-format', rule, {
+			'valid': valid,
+			'invalid': []
+		});
+		t.pass( 'passed without errors' );
+	} catch ( err ) {
+		t.fail( 'encountered an error: ' + err.message );
+	}
+	t.end();
+});
+
+tape( 'the function negatively validates format calls which do not perform string interpolation', function test( t ) {
+	var tester = new RuleTester({
+		'parserOptions': {
+			'ecmaVersion': 2020
+		}
+	});
+
+	try {
+		tester.run( 'no-unnecessary-format', rule, {
+			'valid': [],
+			'invalid': invalid
+		});
+		t.pass( 'passed without errors' );
+	} catch ( err ) {
+		t.fail( 'encountered an error: ' + err.message );
+	}
+	t.end();
+});
+
+tape( 'the function does not validate code not containing checkable format calls', function test( t ) {
+	var tester = new RuleTester({
+		'parserOptions': {
+			'ecmaVersion': 2020
+		}
+	});
+
+	try {
+		tester.run( 'no-unnecessary-format', rule, {
+			'valid': unvalidated,
+			'invalid': []
+		});
+		t.pass( 'passed without errors' );
+	} catch ( err ) {
+		t.fail( 'encountered an error: ' + err.message );
+	}
+	t.end();
+});

From ddddb347e6db44ba1c02f32f7105163b6798362a Mon Sep 17 00:00:00 2001
From: Athan <kgryte@gmail.com>
Date: Mon, 24 Aug 2026 23:31:40 -0700
Subject: [PATCH 2/6] Apply suggestions from code review

Co-authored-by: Athan <kgryte@gmail.com>
Signed-off-by: Athan <kgryte@gmail.com>
---
 .../_tools/eslint/rules/no-unnecessary-format/lib/main.js    | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/lib/main.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/lib/main.js
index 3954c479df12..070e2dc93627 100644
--- a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/lib/main.js
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/lib/main.js
@@ -20,6 +20,7 @@
 
 // MODULES //
 
+var isString = require( '@stdlib/assert/is-string' ).isPrimitive;
 var formatTokenize = require( '@stdlib/string/base/format-tokenize' );
 
 
@@ -80,7 +81,7 @@ function hasPlaceholders( str ) {
 
 	tokens = formatTokenize( str );
 	for ( i = 0; i < tokens.length; i++ ) {
-		if ( typeof tokens[ i ] !== 'string' ) {
+		if ( !isString( tokens[ i ] ) ) {
 			return true;
 		}
 	}
@@ -140,7 +141,7 @@ function main( context ) {
 		if (
 			node.arguments.length === 0 ||
 			node.arguments[ 0 ].type !== 'Literal' ||
-			typeof node.arguments[ 0 ].value !== 'string'
+		!isString( node.arguments[ 0 ].value )
 		) {
 			return;
 		}

From 1e4178291cd737a928fd55253d7d1f9188644b46 Mon Sep 17 00:00:00 2001
From: Athan <kgryte@gmail.com>
Date: Mon, 24 Aug 2026 23:33:16 -0700
Subject: [PATCH 3/6] Apply suggestions from code review

Co-authored-by: Athan <kgryte@gmail.com>
Signed-off-by: Athan <kgryte@gmail.com>
---
 .../_tools/eslint/rules/no-unnecessary-format/lib/main.js       | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/lib/main.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/lib/main.js
index 070e2dc93627..5ac150f61589 100644
--- a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/lib/main.js
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/lib/main.js
@@ -141,7 +141,7 @@ function main( context ) {
 		if (
 			node.arguments.length === 0 ||
 			node.arguments[ 0 ].type !== 'Literal' ||
-		!isString( node.arguments[ 0 ].value )
+			!isString( node.arguments[ 0 ].value )
 		) {
 			return;
 		}

From e0bfde7ff0c53f5b162bc2b2e2c5dee06c4a7e26 Mon Sep 17 00:00:00 2001
From: Athan <kgryte@gmail.com>
Date: Mon, 24 Aug 2026 23:34:42 -0700
Subject: [PATCH 4/6] Apply suggestions from code review

Co-authored-by: Athan <kgryte@gmail.com>
Signed-off-by: Athan <kgryte@gmail.com>
---
 .../no-unnecessary-format/test/fixtures/invalid.js   |  5 +----
 .../test/fixtures/unvalidated.js                     |  4 +---
 .../no-unnecessary-format/test/fixtures/valid.js     | 12 +-----------
 3 files changed, 3 insertions(+), 18 deletions(-)

diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/invalid.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/invalid.js
index 203045515d54..c0d1eab05b00 100644
--- a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/invalid.js
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/invalid.js
@@ -18,11 +18,8 @@
 
 'use strict';
 
-var invalid = [];
-var test;
-
 // Static string...
-test = {
+var test = {
 	'code': [
 		'var format = require( \'@stdlib/string/format\' );',
 		'',
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/unvalidated.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/unvalidated.js
index e39c20a21b43..8ea2ef0edcf1 100644
--- a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/unvalidated.js
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/unvalidated.js
@@ -18,10 +18,8 @@
 
 'use strict';
 
-var unvalidated = [];
-var test;
 
-test = {
+var test = {
 	'code': [
 		'var x = 123;'
 	].join( '\n' )
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/valid.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/valid.js
index 7f25c605455a..75aa3344aab1 100644
--- a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/valid.js
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/valid.js
@@ -10,19 +10,9 @@
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
-* distributed under the License is distributed on an "AS IS" BASIS,
-* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-* See the License for the specific language governing permissions and
-* limitations under the License.
-*/
-
-'use strict';
-
-var valid = [];
-var test;
 
 // Format string with a placeholder...
-test = {
+var test = {
 	'code': [
 		'var format = require( \'@stdlib/string/format\' );',
 		'',

From 45f5668fdb7978a5c36f6c95c3e1366f1b5738a8 Mon Sep 17 00:00:00 2001
From: Athan <kgryte@gmail.com>
Date: Mon, 24 Aug 2026 23:35:10 -0700
Subject: [PATCH 5/6] Apply suggestions from code review

Co-authored-by: Athan <kgryte@gmail.com>
Signed-off-by: Athan <kgryte@gmail.com>
---
 .../eslint/rules/no-unnecessary-format/test/fixtures/invalid.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/invalid.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/invalid.js
index c0d1eab05b00..90153d0bd216 100644
--- a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/invalid.js
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/invalid.js
@@ -18,6 +18,8 @@
 
 'use strict';
 
+var invalid = [];
+
 // Static string...
 var test = {
 	'code': [

From a6834cee35f4059e5c48dcb3b63dd9637f2200da Mon Sep 17 00:00:00 2001
From: Athan <kgryte@gmail.com>
Date: Mon, 24 Aug 2026 23:37:09 -0700
Subject: [PATCH 6/6] Apply suggestions from code review

Co-authored-by: Athan <kgryte@gmail.com>
Signed-off-by: Athan <kgryte@gmail.com>
---
 .../no-unnecessary-format/test/fixtures/unvalidated.js   | 1 +
 .../rules/no-unnecessary-format/test/fixtures/valid.js   | 9 +++++++++
 2 files changed, 10 insertions(+)

diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/unvalidated.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/unvalidated.js
index 8ea2ef0edcf1..168d7f04c106 100644
--- a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/unvalidated.js
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/unvalidated.js
@@ -18,6 +18,7 @@
 
 'use strict';
 
+var unvalidated = [];
 
 var test = {
 	'code': [
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/valid.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/valid.js
index 75aa3344aab1..7ff73f986358 100644
--- a/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/valid.js
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-unnecessary-format/test/fixtures/valid.js
@@ -10,6 +10,15 @@
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+var valid = [];
 
 // Format string with a placeholder...
 var test = {