#37 sepearte out computeCopyrightYears

src/Copyright.js

@@ -50,9 +50,33 @@ module.exports = ( () => {
   class Copyright {
 
     /**
-     * Utility method to generate a copyright statement for a file. The start year is computed from when the file was
+     * Utility method to compute the copyright years for a file. The start year is computed from when the file was
      * checked into git or the current year if it hasn't been checked-in yet. The end year is assumed to be the current
-     * year. Result includes the correct comment delimiters and follows the format described at the top of this file.
+     * year. If the given file path doesn't exist, it will return the current year as a string.
+     * @public
+     *
+     * @param {String} filePath - path of the file, relative to the root directory that invoked the command.
+     * @returns {String} - the copyright years string (e.g. '2019-2020')
+     */
+    static computeCopyrightYears( filePath ) {
+      Util.assert( typeof filePath === 'string', `invalid filePath: ${ filePath }` );
+
+      // Compute the year the file was checked into git as the start year. If it hasn't been checked into git yet, the
+      // start year is the current year. Solution from:
+      // https://stackoverflow.com/questions/2390199/finding-the-date-time-a-file-was-first-added-to-a-git-repository
+      const startYear = shell.exec( `git log --follow --format=%aI -- ${ filePath } | tail -1`, { silent: true } )
+        .trim().split( '-' )[ 0 ] || Util.CURRENT_YEAR;
+
+      const endYear = Util.CURRENT_YEAR; // The end year is assumed to be the current year.
+
+      // Create and return year string or the year range string to use in the copyright statement.
+      return ( parseInt( startYear, 10 ) === endYear ) ? startYear : `${ startYear }-${ endYear }`;
+    }
+
+    /**
+     * Utility method to generate a copyright statement for a file. See computeCopyrightYears() for documentation on how
+     * the copyright years string is computed. Result includes the correct comment delimiters and follows the format
+     * described at the top of this file.
      * @public
      *
      * @param {String} filePath - path of the file, relative to the root directory that invoked the command.
@@ -67,16 +91,8 @@ module.exports = ( () => {
       // Reference to the validated and parsed generator author (see ./Generator.js for more documentation).
       const author = Generator.getReplacementValue( 'AUTHOR' );
 
-      // Compute the year the file was checked into git as the start year. If it hasn't been checked into git yet, the
-      // start year is the current year. Solution from:
-      // https://stackoverflow.com/questions/2390199/finding-the-date-time-a-file-was-first-added-to-a-git-repository
-      const startYear = shell.exec( `git log --follow --format=%aI -- ${ filePath } | tail -1`, { silent: true } )
-        .trim().split( '-' )[ 0 ] || Util.CURRENT_YEAR;
-
-      const endYear = Util.CURRENT_YEAR; // The end year is assumed to be the current year.
-
-      // Create the year string or the year range string to use in the copyright statement.
-      const yearsString = ( parseInt( startYear, 10 ) === endYear ) ? startYear : `${ startYear }-${ endYear }`;
+      // Reference the years string from computeCopyrightYears().
+      const yearsString = this.computeCopyrightYears( filePath );
 
       // Create the copyright line without the comment delimiters first. Then return the parsed value.
       const copyrightContent = `Copyright © ${ yearsString } ${ author }. All rights reserved.`;

src/Generator.js

@@ -35,15 +35,14 @@ module.exports = ( () => {
 
   // constants
   // Object literal that describes the replacement strings in template files to replace. Each key is the replacement
-  // string (without the brackets for now) and correlates with one of the three values stated below:
+  // string (without the brackets for now) and correlates with one of the two values stated below:
   // 1. String[] - nested keys path to the package value. For example, PACKAGE_JSON.foo.bar would have nested keys
   //               [ 'foo', 'bar' ]. PACKAGE_JSON is checked to have the nested keys (see
   //               UserConfig.parseNestedJSONValue()).
   // 2. Object Literal - an object literal with:
   //                      - a path key that correlates to an array of the nested package keys as described in 1.
   //                      - a parse key that correlates to a function that is called to 'parse' a value that is
   //                        retrieved from the package object. The returned value is the replacement value.
-  // 3. * - the actual replacement value to replace the replacement string in the template file.
   const REPLACEMENT_STRINGS_SCHEMA = {
     AUTHOR: [ 'author', 'name' ],
     AUTHOR_EMAIL: [ 'author', 'email' ],
@@ -55,8 +54,7 @@ module.exports = ( () => {
     VERSION: [ 'version' ],
     LICENSE: [ 'license' ],
     GITHUB_URL: { path: [ 'repository', 'url' ], parse: value => value.replace( /.git|git+/i, '' ) },
-    REPO_TITLE: { path: [ 'name' ], parse: value => Util.toTitleCase( value ) },
-    COPYRIGHT_YEARS: Util.CURRENT_YEAR  // Use the current year for now, then use ./Copyright to update after generating
+    REPO_TITLE: { path: [ 'name' ], parse: value => Util.toTitleCase( value ) }
   };
 
   // Object literal that keeps track of the replacement values. This helps performance and ensures that replacement