Add test tags. Resolves #76

CONTRIBUTING.md

@@ -33,6 +33,45 @@ To add or modify tests:
 
 Do not modify `cts.json` directly!
 
+
+### Tags
+
+When adding a new test, please tag it with the appropriate tags. The full list of tags
+is printed (to stderr) when running the build script. Please use the
+existing tags where possible, and add new tags as needed.
+
+You can build a subset of the test suite by specifying the tags you want to include.
+
+_Example 1._ Build only the tests tagged with `index` OR `whitespace` (or both):
+
+``` shell
+node build.js -t index -t whitespace
+```
+
+_Example 2._ Build only the tests tagged with `index` AND `whitespace`:
+
+``` shell
+node build.js -t index -t whitespace -a
+```
+
+Example 3. Build only tests NOT tagged with `index`:
+
+``` shell
+node build.js -t index -e
+```
+
+Example 4. Exclude tests tagged with BOTH `index` AND `whitespace`:
+
+``` shell
+node build.js -t index -t whitespace -t error -e -a
+```
+
+### Checking for potential duplicates
+
+As the test suite grows, it is becoming harder to check for potential duplicates. One way to help with this is to see
+which tests are tagged with the same tags.
+
+
 ### Staying In Sync With Upstream
 
 When your branch gets out of sync with the jsonpath-standard/jsonpath-compliance-test-suite/main branch, use the following to update:

build.js

@@ -1,7 +1,10 @@
+#!/usr/bin/env node
 // @ts-check
 
 const fs = require('fs');
 const path = require('path');
+const {parseArgs} = require('node:util');
+
 /**
  * The file extension of test files.
  * @type {string}
@@ -24,25 +27,85 @@ const testNameSeparator = ', ';
  */
 const description = 'JSONPath Compliance Test Suite. This file is autogenerated, do not edit.';
 
-build();
-
 /**
- * Build a combined test suite from a directory of test files.
- * The output is written to stdout.
+ * The options for the command line. See https://nodejs.org/api/util.html#utilparseargsconfig.
+ * IMPORTANT: Update usage if you change these options.
  */
-function build() {
-    if (process.argv.length < 3) {
-        console.error('Usage: node build.js <test-folder-path>');
+const options = {
+    'tag': {
+        type: 'string',
+        short: 't',
+        multiple: true,
+        default: [],
+    },
+    'require-all': {
+        type: 'boolean',
+        short: 'a',
+        default: false,
+    },
+    'exclude': {
+        type: 'boolean',
+        short: 'e',
+        default: false,
+    }
+}
+
+const usage = [
+    'Build a combined test suite from a directory of test files.',
+    '',
+    'Usage: node build.js <test-folder-path> [OPTION]...',
+    'Options:',
+    '  -t, --tag <tag>      Filter tests by tag. Can be used multiple times.',
+    '                       Any test with at least one matching tag (by default) or all matching tags (if -a is used)',
+    '                       will be included (by default) or excluded (if -e is used) in the output.',
+    '  -a, --require-all    Flag to require all tags to be present in a test.',
+    '  -e, --exclude        Flag to exclude the specified tags instead of including them.',
+]
+
+main()
+
+function main() {
+    const {values, positionals} = parseArgs({options, allowPositionals: true});
+    if (positionals.length !== 1) {
+        usage.forEach(line => console.error(line));
         process.exit(1);
     }
+    const [testsFolder] = positionals;
+    buildTestSuite(testsFolder, values['tag'], values['require-all'], values['exclude']);
+}
 
-    const testsFolder = process.argv[2];
-    const tests = readTestsFromDir(testsFolder);
+/**
+ * Build a combined test suite from a directory of test files.
+ * The output is written to stdout.
+ * @param testsFolder {string} - The directory containing the test files.
+ * @param tags {string[]} - The tags to filter tests by.
+ * @param all {boolean} - True if all tags must match.
+ * @param exclude {boolean} - True if the tags should be excluded instead of included.
+ */
+function buildTestSuite(testsFolder, tags, all, exclude) {
+    console.error(`Building test suite from ${testsFolder}`);
+    console.error(`Filtering by tags (${tags.length}): ${tags.join(', ')}`);
+    console.error(`Require all tags: ${all}`);
+    console.error(`Exclude tags: ${exclude}`);
+    const tagFilter = all
+        ? list => tags.every(t => list.includes(t))
+        : list => tags.some(t => list.includes(t))
+    const tests = readTestsFromDir(testsFolder)
+        .filter(test => tags.length === 0 || (tagFilter(getTags(test)) !== exclude));
+    tests.forEach(test => {
+        if ('tags' in test) test.tags.sort();
+    });
     const cts = {'description': description, 'tests': tests};
     console.log(JSON.stringify(cts, null, jsonIndent));
+    const allTags = Array.from(new Set(tests.flatMap(getTags)));
+    allTags.sort();
     console.error(`Wrote ${tests.length} tests to stdout.`);
-}
+    console.error(`Tags (${allTags.length}): ${allTags.join(', ')}`);
 
+    function getTags(test) {
+        return 'tags' in test ? test.tags : [];
+    }
+}
 
 /**
  * Read all test files from a directory and its subdirectories.