/** * @fileoverview Require or disallow newline at the end of files * @author Nodeca Team <https://github.com/nodeca> */ "use strict"; //------------------------------------------------------------------------------ // Rule Definition //------------------------------------------------------------------------------ /** @type {import('../shared/types').Rule} */ module.exports = { meta: { type: "layout", docs: { description: "Require or disallow newline at the end of files", recommended: false, url: "https://eslint.org/docs/rules/eol-last" }, fixable: "whitespace", schema: [ { enum: ["always", "never", "unix", "windows"] } ], messages: { missing: "Newline required at end of file but not found.", unexpected: "Newline not allowed at end of file." } }, create(context) { //-------------------------------------------------------------------------- // Public //-------------------------------------------------------------------------- return { Program: function checkBadEOF(node) { const sourceCode = context.getSourceCode(), src = sourceCode.getText(), lastLine = sourceCode.lines[sourceCode.lines.length - 1], location = { column: lastLine.length, line: sourceCode.lines.length }, LF = "\n", CRLF = `\r${LF}`, endsWithNewline = src.endsWith(LF); /* * Empty source is always valid: No content in file so we don't * need to lint for a newline on the last line of content. */ if (!src.length) { return; } let mode = context.options[0] || "always", appendCRLF = false; if (mode === "unix") { // `"unix"` should behave exactly as `"always"` mode = "always"; } if (mode === "windows") { // `"windows"` should behave exactly as `"always"`, but append CRLF in the fixer for backwards compatibility mode = "always"; appendCRLF = true; } if (mode === "always" && !endsWithNewline) { // File is not newline-terminated, but should be context.report({ node, loc: location, messageId: "missing", fix(fixer) { return fixer.insertTextAfterRange([0, src.length], appendCRLF ? CRLF : LF); } }); } else if (mode === "never" && endsWithNewline) { const secondLastLine = sourceCode.lines[sourceCode.lines.length - 2]; // File is newline-terminated, but shouldn't be context.report({ node, loc: { start: { line: sourceCode.lines.length - 1, column: secondLastLine.length }, end: { line: sourceCode.lines.length, column: 0 } }, messageId: "unexpected", fix(fixer) { const finalEOLs = /(?:\r?\n)+$/u, match = finalEOLs.exec(sourceCode.text), start = match.index, end = sourceCode.text.length; return fixer.replaceTextRange([start, end], ""); } }); } } }; } };