Add new file-header rule to enforce headers matched by regexp (#1441)

- Checks for comments at the very beginning of files
- Ignores #!
- Matches comment contents with header regexp

src/rules/fileHeaderRule.ts

@@ -0,0 +1,61 @@
+import * as ts from "typescript";
+
+import * as Lint from "../lint";
+
+export class Rule extends Lint.Rules.AbstractRule {
+    /* tslint:disable:object-literal-sort-keys */
+    public static metadata: Lint.IRuleMetadata = {
+        ruleName: "file-header",
+        description: "Enforces a certain header comment for all files, matched by a regular expression.",
+        optionsDescription: "Regular expression to match the header.",
+        options: {
+            type: "string",
+        },
+        optionExamples: ['"true", "Copyright \\d{4}"'],
+        type: "style",
+    };
+    /* tslint:enable:object-literal-sort-keys */
+
+    public static FAILURE_STRING = "missing file header";
+
+    public apply(sourceFile: ts.SourceFile): Lint.RuleFailure[] {
+        const walker = new FileHeaderWalker(sourceFile, this.getOptions());
+        const options = this.getOptions().ruleArguments;
+        walker.setRegexp(new RegExp(options[0].toString()));
+        return this.applyWithWalker(walker);
+    }
+}
+
+class FileHeaderWalker extends Lint.RuleWalker {
+    // match a single line or multi line comment with leading whitespace
+    // the wildcard dot does not match new lines - we can use [\s\S] instead
+    private commentRegexp: RegExp = /^\s*(\/\/(.*?)|\/\*([\s\S]*?)\*\/)/;
+    private headerRegexp: RegExp;
+
+    public setRegexp(headerRegexp: RegExp) {
+        this.headerRegexp = headerRegexp;
+    }
+
+    public visitSourceFile(node: ts.SourceFile) {
+        if (this.headerRegexp) {
+            let text = node.getFullText();
+            let offset = 0;
+            // ignore shebang if it exists
+            if (text.indexOf("#!") === 0) {
+                offset = text.indexOf("\n") + 1;
+                text = text.substring(offset);
+            }
+            // check for a comment
+            const match = text.match(this.commentRegexp);
+            if (!match) {
+                this.addFailure(this.createFailure(offset, 0, Rule.FAILURE_STRING));
+            } else {
+                // either the third or fourth capture group contains the comment contents
+                const comment = match[2] ? match[2] : match[3];
+                if (comment.search(this.headerRegexp) < 0) {
+                    this.addFailure(this.createFailure(offset, 0, Rule.FAILURE_STRING));
+                }
+            }
+        }
+    }
+}

src/tsconfig.json

@@ -77,6 +77,7 @@
         "rules/commentFormatRule.ts",
         "rules/curlyRule.ts",
         "rules/eoflineRule.ts",
+        "rules/fileHeaderRule.ts",
         "rules/forinRule.ts",
         "rules/indentRule.ts",
         "rules/interfaceNameRule.ts",

test/rules/file-header/bad-shebang/test.ts.lint

@@ -0,0 +1,18 @@
+#!/usr/bin/env node
+
+~nil [missing file header]
+/*
+ * Bad header 3
+ */
+
+export class A {
+    public x = 1;
+
+    public B() {
+        return 2;
+    }
+}
+
+/*
+ * Good header 4
+ */

test/rules/file-header/bad-shebang/tslint.json

@@ -0,0 +1,5 @@
+{
+    "rules": {
+        "file-header": [true, "Good header \\d"]
+    }
+}

test/rules/file-header/bad-use-strict/test.ts.lint

@@ -0,0 +1,18 @@
+"use strict";
+~nil [missing file header]
+
+/*
+ * Bad header 5
+ */
+
+export class A {
+    public x = 1;
+
+    public B() {
+        return 2;
+    }
+}
+
+/*
+ * Good header 6
+ */

test/rules/file-header/bad-use-strict/tslint.json

@@ -0,0 +1,5 @@
+{
+    "rules": {
+        "file-header": [true, "Good header \\d"]
+    }
+}

test/rules/file-header/bad/test.ts.lint

@@ -0,0 +1,16 @@
+/*
+~nil [missing file header]
+ * Bad header 1
+ */
+
+export class A {
+    public x = 1;
+
+    public B() {
+        return 2;
+    }
+}
+
+/*
+ * Good header 2
+ */

test/rules/file-header/bad/tslint.json

@@ -0,0 +1,5 @@
+{
+    "rules": {
+        "file-header": [true, "Good header \\d"]
+    }
+}

test/rules/file-header/good-shebang/test.ts.lint

@@ -0,0 +1,14 @@
+#!/usr/bin/env node
+
+
+/*
+ * Good header 2
+ */
+
+export class A {
+    public x = 1;
+
+    public B() {
+        return 2;
+    }
+}

test/rules/file-header/good-shebang/tslint.json

@@ -0,0 +1,5 @@
+{
+    "rules": {
+        "file-header": [true, "Good header \\d"]
+    }
+}

test/rules/file-header/good-use-strict/test.ts.lint

@@ -0,0 +1,13 @@
+/*
+ * Good header 3
+ */
+
+"use strict";
+
+export class A {
+    public x = 1;
+
+    public B() {
+        return 2;
+    }
+}

test/rules/file-header/good-use-strict/tslint.json

@@ -0,0 +1,5 @@
+{
+    "rules": {
+        "file-header": [true, "Good header \\d"]
+    }
+}

test/rules/file-header/good/test.ts.lint

@@ -0,0 +1,12 @@
+
+/*
+ * Good header 1
+ */
+
+export class A {
+    public x = 1;
+
+    public B() {
+        return 2;
+    }
+}

test/rules/file-header/good/tslint.json

@@ -0,0 +1,5 @@
+{
+    "rules": {
+        "file-header": [true, "Good header \\d"]
+    }
+}

test/tsconfig.json

@@ -73,6 +73,7 @@
         "../src/rules/commentFormatRule.ts",
         "../src/rules/curlyRule.ts",
         "../src/rules/eoflineRule.ts",
+        "../src/rules/fileHeaderRule.ts",
         "../src/rules/forinRule.ts",
         "../src/rules/indentRule.ts",
         "../src/rules/interfaceNameRule.ts",