commit fd580bda03ed76d82f0f16a2f48fd50ebaa9bf7f
Author: olemorud <ole.kristian.morud@cern.ch>
Date:   Tue Mar 14 12:58:38 2023 +0100

    Initial commit

diff --git a/README.md b/README.md
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+# GCC problem matcher
+
+Creates annotations for warnings and errors in gcc builds.
+
+
+## Usage
+
+Just add a single line before running the build step.
+
+```yaml
+    - uses: olemorud/gcc-problem-matcher@master
+```
diff --git a/action.yml b/action.yml
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+++ b/action.yml
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+name: GCC Problem Matcher
+
+description: Get annotations for warnings and errors on builds using gcc
+
+author: Ole Morud
+
+branding:
+  icon: search
+  color: yellow
+
+inputs:
+  root:
+    description: 'base directory for build, e.g. /workdir/build'
+    required: false
+    default: ''
+
+runs:
+  using: 'node16'
+  main: 'src/index.js'
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diff --git a/src/gcc_matcher.jsontemplate b/src/gcc_matcher.jsontemplate
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+{
+    "problemMatcher": [
+        {
+            "owner": "gcc-problem-matcher",
+            "pattern": [
+                {
+                    "regexp": "^${{ BASE }}\/?(.*?):(\\d+):(\\d*):?\\s+(?:fatal\\s+)?(warning|error):\\s+(.*)$",
+                    "file": 1,
+                    "line": 2,
+                    "column": 3,
+                    "severity": 4,
+                    "message": 5
+                }
+            ]
+        }
+    ]
+}
diff --git a/src/index.js b/src/index.js
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+++ b/src/index.js
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+const path = require('path');
+const fs = require('node:fs');
+//const core = require('@actions/core');
+
+// C:\Users\ => C\:\\Users\\
+const escapeRegExp = (s) =>
+	s.replace(/[:.*+?^${}()|\/[\]\\]/g, "\\$&");
+
+
+// ${{ key }}, ${{var}}, ${{ aggqq43g3qg4 }}
+const variable = (key) =>
+	new RegExp("\\${{\\s*?" + key + "\\s*?}}", "g");
+
+
+// default value set in /action.yml
+// const root = core.getInput('root', { required: false });
+root = '/tmp/workspace';
+
+const templatePath = path.join(__dirname, "gcc_matcher.jsontemplate");
+
+const parsed = 
+	fs.readFileSync(templatePath, "ascii")
+		.replace(variable("BASE"), escapeRegExp(root));
+
+const matcherPath = path.join(__dirname, "gcc_matcher.json");
+
+fs.writeFileSync(matcherPath, parsed);
+
+console.log('::add-matcher::' + matcherPath);
+
+/* for testing */ 
+exports.escapeRegExp = escapeRegExp
+exports.variable = variable;
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diff --git a/test/unittest.js b/test/unittest.js
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+++ b/test/unittest.js
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+const assert = require('node:assert');
+const test = require('node:test');
+const _testing = require('../src/index');
+
+test('regex escaping test', () => {
+    const escapeRegExp = _testing.escapeRegExp;
+
+    const st = [
+        {str: "C:\\Users\\", ok: "C\\:\\\\Users\\\\"},
+        {str: "/usr/bin/",   ok: "\\/usr\\/bin\\/"},
+        {str: "(\\\\d+):",   ok: "\\(\\\\\\\\d\\+\\)\\:"}
+    ];
+
+    st.forEach( (x) => {
+        const result = escapeRegExp(x.str);
+        console.log(result, x.ok);
+        assert.strictEqual(result, x.ok);
+    });
+});
+
+test('variable regex matching test', () => {
+    const variable = _testing.variable;
+
+    const expected = [
+        {needle: "foo", haystack: "this sentence contains variable ${{foo}}", ok: true},
+        {needle: "bar", haystack: "finds \n ${{bar}} \n in multilines", ok: true},
+        {needle: "baz", haystack: "${{    baz  }}", ok: true},
+        {needle: "",    haystack: "${{aaa}}", ok: false},
+        {needle: "bad", haystack: "{{bad}}", ok: false},
+        {needle: "",    haystack: "${{}}", ok: true},
+    ];
+
+    expected.forEach( (x) => {
+        console.log(x);
+        const match = x.haystack.match(variable(x.needle));
+        assert.strictEqual( match !== null, x.ok );
+    });
+});