Add configureNightly script.

.gitignore

@@ -25,6 +25,7 @@ tests/baselines/reference/projectOutput/*
 tests/baselines/local/projectOutput/*
 tests/services/baselines/prototyping/local/*
 tests/services/browser/typescriptServices.js
+scripts/configureNightly.js
 scripts/processDiagnosticMessages.d.ts
 scripts/processDiagnosticMessages.js
 scripts/importDefinitelyTypedTests.js

scripts/configureNightly.ts

@@ -0,0 +1,69 @@
+/// <reference path="../src/compiler/sys.ts" />
+
+/**
+ * A minimal description for a parsed package.json object.
+ */
+interface PackageJson {
+    name: string;
+    version: string;
+    keywords: string[];
+}
+
+function main(): void {
+    const sys = ts.sys;
+    if (sys.args.length < 2) {
+        sys.write("Usage:" + sys.newLine)
+        sys.write("\tnode configureNightly.js <package.json location> <file containing version>" + sys.newLine);
+        return;
+    }
+
+    // Acquire the version from the package.json file and modify it appropriately.
+    const packageJsonFilePath = ts.normalizePath(sys.args[0]);
+    const packageJsonContents = sys.readFile(packageJsonFilePath);
+    const packageJsonValue: PackageJson = JSON.parse(packageJsonContents);
+
+    const nightlyVersion = getNightlyVersionString(packageJsonValue.version);
+
+    // Modify the package.json structure
+    packageJsonValue.version = nightlyVersion;
+
+    if (packageJsonValue.name !== "typescript-nightly") {
+        packageJsonValue.name = "typescript-nightly";
+        packageJsonValue.keywords.push("nightly", "alpha", "beta", "prerelease");
+    }
+
+    // Acquire and modify the source file that exposes the version string.
+    const tsFilePath = ts.normalizePath(sys.args[1]);
+    const tsFileContents = sys.readFile(tsFilePath);
+    const versionAssignmentRegExp = /export\s+const\s+version\s+=\s+".*";/;
+    const modifiedTsFileContents = tsFileContents.replace(versionAssignmentRegExp, `export const version = "${nightlyVersion}";`);
+
+    // Ensure we are actually changing something - the user probably wants to know that the update failed.
+    if (tsFileContents === modifiedTsFileContents) {
+        throw `File '${tsFilePath}' did not contain pattern ${versionAssignmentRegExp}`;
+    }
+
+    // Finally write the changes to disk.
+    sys.writeFile(packageJsonFilePath, JSON.stringify(packageJsonValue, /*replacer:*/ undefined, /*space:*/ 4))
+    sys.writeFile(tsFilePath, modifiedTsFileContents);
+}
+
+function getNightlyVersionString(versionString: string): string {
+    // If the version string already contains "-nightly",
+    // then get the base string and update based on that.
+    const dashNightlyPos = versionString.indexOf("-nightly");
+    if (dashNightlyPos >= 0) {
+        versionString = versionString.slice(0, dashNightlyPos);
+    }
+
+    // We're going to append a representation of the current time at the end of the current version.
+    // String.prototype.toISOString() returns a 24-character string formatted as 'YYYY-MM-DDTHH:mm:ss.sssZ',
+    // but we'd prefer to just use hyphens as separators instead of 'T', ':', and '.'.
+    // The trailing 'Z' in this string can be removed; UTC time will always be implicit here.
+    const now = new Date();
+    const timeStr = now.toISOString().slice(0, -1).replace(/:|T|\./g, "-");
+
+    return `${versionString}-nightly-${timeStr}`;
+}
+
+main();