✨ Add pre-parse hook to rewrite arguments

src/funcs/parseArguments.ts

@@ -20,10 +20,12 @@ interface IOption {
  * Checks the command line arguments against the given specification, and returns the arguments as a JavaScript object, as well as a failure function that prints the usage instructions before terminating.
  * If an error is found, outputs an error message and terminates with a non-zero exit code.
  * @param spec A specification of what arguments are expected.
+ * @param preParseHook Optionally, a function to modify the command line arguments before parsing them.
  */
-export default function parseArguments(spec: { [key: string]: IOption }): { fail: (errorMessage: string) => void, args: { [key: string]: string } } {
-  //The original arguments from the command line
-  const args = process.argv.slice(2);
+export default function parseArguments(
+    spec: { [key: string]: IOption },
+    preParseHook?: (args: string[], fail: (message: string) => void) => (string[] | undefined),
+  ): { fail: (errorMessage: string) => void, args: { [key: string]: string } } {
   //The parsed arguments that are returned by this function
   const outputArgs: { [key: string]: string } = {};
 
@@ -69,6 +71,21 @@ export default function parseArguments(spec: { [key: string]: IOption }): { fail
 
   const failFunction = failWithError.bind(null, usage);
 
+  //The original arguments from the command line
+  let args = process.argv.slice(2);
+
+  //If defined, run the pre-parse hook to modify the arguments
+  if (preParseHook !== undefined) {
+    try {
+      const modifiedArgs = preParseHook(args, failFunction);
+      if (modifiedArgs !== undefined) {
+        args = modifiedArgs;
+      }
+    } catch (error) {
+      failFunction(`Could not run pre-parse hook, encountered error: ${String(error)}.`);
+    }
+  }
+
   function parseValue(argumentValue: string) {
     //Verify value for correctness
     const verifyFunc = spec[argumentOption].verify;

src/getManifest.ts

@@ -5,7 +5,7 @@ import parseArguments from './funcs/parseArguments';
 
 const { args, fail } = parseArguments({
   product: { short: 'p', description: 'Name of the product we want to get the manifest on', verify: verifyProductName, message: (value) => `"${value}" is not a valid product name.` },
-});
+}, (origArgs) => ((origArgs.length === 1) ? ['--product', origArgs[0]] : undefined));
 
 //Get manifest and write output to stdout
 getManifest(args.product as Product).then((output: IManifest) => {

src/getPatchZip.ts

@@ -7,7 +7,7 @@ const { args, fail } = parseArguments({
   product: { short: 'p', description: 'Name of the product we want to get the patch info on', verify: verifyProductName, message: (value) => `"${value}" is not a valid product name.` },
   from: { short: 'f', description: 'Number of the from release, must be an integer in the range [-1, 999]', verify: (str) => str.match(/^(-1|0|[1-9][0-9]{0,2})$/) !== null },
   to: { short: 't', description: 'Number of the to release, must be an integer in the range [0, 999]', verify: (str) => str.match(/^(0|[1-9][0-9]{0,2})$/) !== null },
-});
+}, (origArgs) => ((origArgs.length === 3) ? ['--product', origArgs[0], '--from', origArgs[1], '--to', origArgs[2]] : undefined));
 
 //Get the .zip file from this patch and write output to stdout
 getPatchZip(args.product as Product, Number(args.from), Number(args.to)).then((output: ISsnFileEntry[]) => {

src/getSolidpkg.ts

@@ -7,7 +7,7 @@ const { args, fail } = parseArguments({
   product: { short: 'p', description: 'Name of the product we want to get the solidpkg on', verify: verifyProductName, message: (value) => `"${value}" is not a valid product name.` },
   from: { short: 'f', description: 'Number of the from release, must be an integer in the range [-1, 999]', verify: (str) => str.match(/^(-1|0|[1-9][0-9]{0,2})$/) !== null },
   to: { short: 't', description: 'Number of the to release, must be an integer in the range [0, 999]', verify: (str) => str.match(/^(0|[1-9][0-9]{0,2})$/) !== null },
-});
+}, (origArgs) => ((origArgs.length === 3) ? ['--product', origArgs[0], '--from', origArgs[1], '--to', origArgs[2]] : undefined));
 
 //Get solidpkg and write output to stdout
 getSolidpkg(args.product as Product, Number(args.from), Number(args.to)).then((output: ISolidSimple) => {