Add options validator (refs #2179)

lib/validate-options.js

@@ -0,0 +1,99 @@
+/**
+ * @fileoverview Validates rule options.
+ * @author Brandon Mills
+ * @copyright 2015 Brandon Mills
+ */
+
+"use strict";
+
+var rules = require("./rules"),
+    validator = require("is-my-json-valid");
+
+var validators = Object.create(null); // Cache generated schema validators
+
+/**
+ * Converts a rule's exported, abbreviated schema into a full schema.
+ * @param {object} options Exported schema from a rule.
+ * @returns {object} Full schema ready for validation.
+ */
+function makeSchema(options) {
+
+    // If no schema, only validate warning level, and permit anything after
+    if (!options) {
+        return {
+            "type": "array",
+            "items": [
+                {
+                    "enum": [0, 1, 2]
+                }
+            ],
+            "minItems": 1
+        };
+    }
+
+    // Given a tuple of schemas, insert warning level at the beginning
+    if (Array.isArray(options)) {
+        return {
+            "type": "array",
+            "items": [
+                {
+                    "enum": [0, 1, 2]
+                }
+            ].concat(options),
+            "minItems": 1,
+            "maxItems": options.length + 1
+        };
+    }
+
+    // Given a full schema, leave it alone
+    return options;
+}
+
+/**
+ * Gets an options schema for a rule.
+ * @param {string} id The rule's unique name.
+ * @returns {object}  vJSON Schema for the rule's options.
+ */
+function getRuleSchema(id) {
+    var rule = rules.get(id);
+    return makeSchema(rule && rule.schema);
+}
+
+/**
+ * Validates a rule's options against its schema.
+ * @param {string} id The rule's unique name.
+ * @param {object} config The given options for the rule.
+ * @param {string} source The name of the configuration source.
+ * @returns {void}
+ */
+module.exports = function (id, config, source) {
+    var validate = validators[id],
+        message;
+
+    if (!validate) {
+        validate = validator(getRuleSchema(id), { verbose: true });
+        validators[id] = validate;
+    }
+
+    if (typeof config === "number") {
+        config = [config];
+    }
+
+    validate(config);
+
+    if (validate.errors) {
+        message = [
+            source, ":\n",
+            "\tConfiguration for rule \"", id, "\" is invalid:\n"
+        ];
+        validate.errors.forEach(function (error) {
+            message.push(
+                "\tValue \"", error.value, "\" ", error.message, ".\n"
+            );
+        });
+
+        throw new Error(message.join(""));
+    }
+};
+
+module.exports.getRuleSchema = getRuleSchema;

tests/lib/validate-options.js

@@ -0,0 +1,74 @@
+/**
+ * @fileoverview Tests for validate-options.
+ * @author Brandon Mills
+ * @copyright 2015 Brandon Mills
+ */
+
+"use strict";
+
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+var assert = require("chai").assert,
+    eslint = require("../../lib/eslint"),
+    validate = require("../../lib/validate-options");
+
+//------------------------------------------------------------------------------
+// Tests
+//------------------------------------------------------------------------------
+
+function mockRule(context) {
+    return {
+        "Program": function(node) {
+            context.report(node, "Expected a validation error.");
+        }
+    };
+}
+
+mockRule.schema = [
+    {
+        "enum": ["single", "double", "backtick"]
+    },
+    {
+        "enum": ["avoid-escape"]
+    }
+];
+
+describe("ValidateOptions", function() {
+
+    beforeEach(function() {
+        eslint.defineRule("mock-rule", mockRule);
+    });
+
+    it("should throw for incorrect warning level", function() {
+        var fn = validate.bind(null, "mock-rule", 3, "tests");
+
+        assert.throws(fn, "tests:\n\tConfiguration for rule \"mock-rule\" is invalid:\n\tValue \"3\" must be an enum value.\n");
+    });
+
+    it("should only check warning level for nonexistent rules", function() {
+        var fn = validate.bind(null, "non-existent-rule", [3, "foobar"], "tests");
+
+        assert.throws(fn, "tests:\n\tConfiguration for rule \"non-existent-rule\" is invalid:\n\tValue \"3\" must be an enum value.\n");
+    });
+
+    it("should only check warning level for plugin rules", function() {
+        var fn = validate.bind(null, "plugin/rule", 3, "tests");
+
+        assert.throws(fn, "tests:\n\tConfiguration for rule \"plugin/rule\" is invalid:\n\tValue \"3\" must be an enum value.\n");
+    });
+
+    it("should throw for incorrect configuration values", function() {
+        var fn = validate.bind(null, "mock-rule", [2, "doulbe", "avoidEscape"], "tests");
+
+        assert.throws(fn, "tests:\n\tConfiguration for rule \"mock-rule\" is invalid:\n\tValue \"doulbe\" must be an enum value.\n\tValue \"avoidEscape\" must be an enum value.\n");
+    });
+
+    it("should throw for too many configuration values", function() {
+        var fn = validate.bind(null, "mock-rule", [2, "single", "avoid-escape", "extra"], "tests");
+
+        assert.throws(fn, "tests:\n\tConfiguration for rule \"mock-rule\" is invalid:\n\tValue \"2,single,avoid-escape,extra\" has more items than allowed.\n");
+    });
+
+});