vendor eslint formatters

- copied the current version of eslint formatters into our codebase
  since they're no longer accesible from importing the `eslint` package
  (see discussions in protofire#380) for
  details
- only imported those already supported, there are many other eslint
  formatters in the current eslint version (8.32.0) than there were in
  the one we were using previously (5.6.0)
- table formatter was dropped by the latest version of eslint, so I
  fetched it from 5.6.0 instead
- while building this commit I realized it was possible to remove a
  formatter entirely and all existing tests would pass, so I created an
  issue for discussing that
- made eslint a dev dependency to reduce install size, since it's only
  used for linting this codebase.
- added some dependencies of the eslint formatters. Used 'old'
  strip-ansi version 6.0.1 which seems to still be maintained instead of
  7.0.1 since from version 7 onwards it's a pure ESM package

lib/formatters/stylish.js

@@ -0,0 +1,101 @@
+/**
+ * @fileoverview Stylish reporter
+ * @author Sindre Sorhus
+ */
+"use strict";
+
+const chalk = require("chalk"),
+    stripAnsi = require("strip-ansi"),
+    table = require("text-table");
+
+//------------------------------------------------------------------------------
+// Helpers
+//------------------------------------------------------------------------------
+
+/**
+ * Given a word and a count, append an s if count is not one.
+ * @param {string} word A word in its singular form.
+ * @param {int} count A number controlling whether word should be pluralized.
+ * @returns {string} The original word with an s on the end if count is not one.
+ */
+function pluralize(word, count) {
+    return (count === 1 ? word : `${word}s`);
+}
+
+//------------------------------------------------------------------------------
+// Public Interface
+//------------------------------------------------------------------------------
+
+module.exports = function(results) {
+
+    let output = "\n",
+        errorCount = 0,
+        warningCount = 0,
+        fixableErrorCount = 0,
+        fixableWarningCount = 0,
+        summaryColor = "yellow";
+
+    results.forEach(result => {
+        const messages = result.messages;
+
+        if (messages.length === 0) {
+            return;
+        }
+
+        errorCount += result.errorCount;
+        warningCount += result.warningCount;
+        fixableErrorCount += result.fixableErrorCount;
+        fixableWarningCount += result.fixableWarningCount;
+
+        output += `${chalk.underline(result.filePath)}\n`;
+
+        output += `${table(
+            messages.map(message => {
+                let messageType;
+
+                if (message.fatal || message.severity === 2) {
+                    messageType = chalk.red("error");
+                    summaryColor = "red";
+                } else {
+                    messageType = chalk.yellow("warning");
+                }
+
+                return [
+                    "",
+                    message.line || 0,
+                    message.column || 0,
+                    messageType,
+                    message.message.replace(/([^ ])\.$/u, "$1"),
+                    chalk.dim(message.ruleId || "")
+                ];
+            }),
+            {
+                align: ["", "r", "l"],
+                stringLength(str) {
+                    return stripAnsi(str).length;
+                }
+            }
+        ).split("\n").map(el => el.replace(/(\d+)\s+(\d+)/u, (m, p1, p2) => chalk.dim(`${p1}:${p2}`))).join("\n")}\n\n`;
+    });
+
+    const total = errorCount + warningCount;
+
+    if (total > 0) {
+        output += chalk[summaryColor].bold([
+            "\u2716 ", total, pluralize(" problem", total),
+            " (", errorCount, pluralize(" error", errorCount), ", ",
+            warningCount, pluralize(" warning", warningCount), ")\n"
+        ].join(""));
+
+        if (fixableErrorCount > 0 || fixableWarningCount > 0) {
+            output += chalk[summaryColor].bold([
+                "  ", fixableErrorCount, pluralize(" error", fixableErrorCount), " and ",
+                fixableWarningCount, pluralize(" warning", fixableWarningCount),
+                " potentially fixable with the `--fix` option.\n"
+            ].join(""));
+        }
+    }
+
+    // Resets output color, for prevent change on top level
+    return total > 0 ? chalk.reset(output) : "";
+};

lib/formatters/table.js

@@ -0,0 +1,150 @@
+/**
+ * @fileoverview "table reporter.
+ * @author Gajus Kuizinas <[email protected]>
+ */
+"use strict";
+
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+const chalk = require("chalk"),
+    table = require("table").table,
+    pluralize = require("pluralize");
+
+//------------------------------------------------------------------------------
+// Helpers
+//------------------------------------------------------------------------------
+
+/**
+ * Draws text table.
+ * @param {Array<Object>} messages Error messages relating to a specific file.
+ * @returns {string} A text table.
+ */
+function drawTable(messages) {
+    const rows = [];
+
+    if (messages.length === 0) {
+        return "";
+    }
+
+    rows.push([
+        chalk.bold("Line"),
+        chalk.bold("Column"),
+        chalk.bold("Type"),
+        chalk.bold("Message"),
+        chalk.bold("Rule ID")
+    ]);
+
+    messages.forEach(message => {
+        let messageType;
+
+        if (message.fatal || message.severity === 2) {
+            messageType = chalk.red("error");
+        } else {
+            messageType = chalk.yellow("warning");
+        }
+
+        rows.push([
+            message.line || 0,
+            message.column || 0,
+            messageType,
+            message.message,
+            message.ruleId || ""
+        ]);
+    });
+
+    return table(rows, {
+        columns: {
+            0: {
+                width: 8,
+                wrapWord: true
+            },
+            1: {
+                width: 8,
+                wrapWord: true
+            },
+            2: {
+                width: 8,
+                wrapWord: true
+            },
+            3: {
+                paddingRight: 5,
+                width: 50,
+                wrapWord: true
+            },
+            4: {
+                width: 20,
+                wrapWord: true
+            }
+        },
+        drawHorizontalLine(index) {
+            return index === 1;
+        }
+    });
+}
+
+/**
+ * Draws a report (multiple tables).
+ * @param {Array} results Report results for every file.
+ * @returns {string} A column of text tables.
+ */
+function drawReport(results) {
+    let files;
+
+    files = results.map(result => {
+        if (!result.messages.length) {
+            return "";
+        }
+
+        return `\n${result.filePath}\n\n${drawTable(result.messages)}`;
+    });
+
+    files = files.filter(content => content.trim());
+
+    return files.join("");
+}
+
+//------------------------------------------------------------------------------
+// Public Interface
+//------------------------------------------------------------------------------
+
+module.exports = function(report) {
+    let result,
+        errorCount,
+        warningCount;
+
+    result = "";
+    errorCount = 0;
+    warningCount = 0;
+
+    report.forEach(fileReport => {
+        errorCount += fileReport.errorCount;
+        warningCount += fileReport.warningCount;
+    });
+
+    if (errorCount || warningCount) {
+        result = drawReport(report);
+    }
+
+    result += `\n${table([
+        [
+            chalk.red(pluralize("Error", errorCount, true))
+        ],
+        [
+            chalk.yellow(pluralize("Warning", warningCount, true))
+        ]
+    ], {
+        columns: {
+            0: {
+                width: 110,
+                wrapWord: true
+            }
+        },
+        drawHorizontalLine() {
+            return true;
+        }
+    })}`;
+
+    return result;
+};

lib/formatters/tap.js

@@ -0,0 +1,95 @@
+/**
+ * @fileoverview TAP reporter
+ * @author Jonathan Kingston
+ */
+"use strict";
+
+const yaml = require("js-yaml");
+
+//------------------------------------------------------------------------------
+// Helper Functions
+//------------------------------------------------------------------------------
+
+/**
+ * Returns a canonical error level string based upon the error message passed in.
+ * @param {Object} message Individual error message provided by eslint
+ * @returns {string} Error level string
+ */
+function getMessageType(message) {
+    if (message.fatal || message.severity === 2) {
+        return "error";
+    }
+    return "warning";
+}
+
+/**
+ * Takes in a JavaScript object and outputs a TAP diagnostics string
+ * @param {Object} diagnostic JavaScript object to be embedded as YAML into output.
+ * @returns {string} diagnostics string with YAML embedded - TAP version 13 compliant
+ */
+function outputDiagnostics(diagnostic) {
+    const prefix = "  ";
+    let output = `${prefix}---\n`;
+
+    output += prefix + yaml.dump(diagnostic).split("\n").join(`\n${prefix}`);
+    output += "...\n";
+    return output;
+}
+
+//------------------------------------------------------------------------------
+// Public Interface
+//------------------------------------------------------------------------------
+
+module.exports = function(results) {
+    let output = `TAP version 13\n1..${results.length}\n`;
+
+    results.forEach((result, id) => {
+        const messages = result.messages;
+        let testResult = "ok";
+        let diagnostics = {};
+
+        if (messages.length > 0) {
+            messages.forEach(message => {
+                const severity = getMessageType(message);
+                const diagnostic = {
+                    message: message.message,
+                    severity,
+                    data: {
+                        line: message.line || 0,
+                        column: message.column || 0,
+                        ruleId: message.ruleId || ""
+                    }
+                };
+
+                // This ensures a warning message is not flagged as error
+                if (severity === "error") {
+                    testResult = "not ok";
+                }
+
+                /*
+                 * If we have multiple messages place them under a messages key
+                 * The first error will be logged as message key
+                 * This is to adhere to TAP 13 loosely defined specification of having a message key
+                 */
+                if ("message" in diagnostics) {
+                    if (typeof diagnostics.messages === "undefined") {
+                        diagnostics.messages = [];
+                    }
+                    diagnostics.messages.push(diagnostic);
+                } else {
+                    diagnostics = diagnostic;
+                }
+            });
+        }
+
+        output += `${testResult} ${id + 1} - ${result.filePath}\n`;
+
+        // If we have an error include diagnostics
+        if (messages.length > 0) {
+            output += outputDiagnostics(diagnostics);
+        }
+
+    });
+
+    return output;
+};