some code cleanup

src/cli/parse-flags.ts

@@ -83,7 +83,7 @@ export const parseFlags = (args: string[], _sys?: CompilerSystem): ConfigFlags =
  *                 | /^[a-zA-Z0-9]+$/ ;
  *
  * There are additional constraints (not shown in the grammar for brevity's sake)
- * on the type of CLIValue which will be associated with a particular argument.
+ * on the type of `CLIValue` which will be associated with a particular argument.
  * We enforce this by declaring lists of boolean, string, etc arguments and
  * checking that types of values before setting them.
  *
@@ -177,7 +177,7 @@ const parseCLITerm = (flags: ConfigFlags, args: string[]) => {
 
 /**
  * Normalize a 'negative' flag name, just to do a little pre-processing before
- * we pass it to `setValue`.
+ * we pass it to `setCLIArg`.
  *
  * @param flagName the flag name to normalize
  * @returns a normalized flag name
@@ -215,7 +215,8 @@ const normalizeFlagName = (flagName: string): string => {
  *
  * @param flags a {@link ConfigFlags} object
  * @param rawArg the raw argument name matched by the parser
- * @param normalizedArg an argument with leading control characters (`--`, `--no-`, etc) removed
+ * @param normalizedArg an argument with leading control characters (`--`,
+ * `--no-`, etc) removed
  * @param value the raw value to be set onto the config flags object
  */
 const setCLIArg = (flags: ConfigFlags, rawArg: string, normalizedArg: string, value: CLIValueResult) => {
@@ -228,21 +229,15 @@ const setCLIArg = (flags: ConfigFlags, rawArg: string, normalizedArg: string, va
         : // no value was supplied, default to true
           true;
     flags.knownArgs.push(rawArg);
-    return;
-  }
-
-  if (readOnlyArrayHasStringMember(STRING_CLI_FLAGS, normalizedArg)) {
+  } else if (readOnlyArrayHasStringMember(STRING_CLI_FLAGS, normalizedArg)) {
     if (typeof value === 'string') {
       flags[normalizedArg] = value;
       flags.knownArgs.push(rawArg);
       flags.knownArgs.push(value);
     } else {
       throwCLIParsingError(rawArg, 'expected a string argument but received nothing');
     }
-    return;
-  }
-
-  if (readOnlyArrayHasStringMember(STRING_ARRAY_CLI_FLAGS, normalizedArg)) {
+  } else if (readOnlyArrayHasStringMember(STRING_ARRAY_CLI_FLAGS, normalizedArg)) {
     if (typeof value === 'string') {
       if (!Array.isArray(flags[normalizedArg])) {
         flags[normalizedArg] = [];
@@ -261,10 +256,7 @@ const setCLIArg = (flags: ConfigFlags, rawArg: string, normalizedArg: string, va
     } else {
       throwCLIParsingError(rawArg, 'expected a string argument but received nothing');
     }
-    return;
-  }
-
-  if (readOnlyArrayHasStringMember(NUMBER_CLI_FLAGS, normalizedArg)) {
+  } else if (readOnlyArrayHasStringMember(NUMBER_CLI_FLAGS, normalizedArg)) {
     if (typeof value === 'string') {
       const parsed = parseInt(value, 10);
 
@@ -280,10 +272,7 @@ const setCLIArg = (flags: ConfigFlags, rawArg: string, normalizedArg: string, va
     } else {
       throwCLIParsingError(rawArg, 'expected a number argument but received nothing');
     }
-    return;
-  }
-
-  if (readOnlyArrayHasStringMember(STRING_NUMBER_CLI_FLAGS, normalizedArg)) {
+  } else if (readOnlyArrayHasStringMember(STRING_NUMBER_CLI_FLAGS, normalizedArg)) {
     if (typeof value === 'string') {
       if (CLI_ARG_STRING_REGEX.test(value)) {
         // if it matches the regex we treat it like a string
@@ -306,10 +295,7 @@ const setCLIArg = (flags: ConfigFlags, rawArg: string, normalizedArg: string, va
     } else {
       throwCLIParsingError(rawArg, 'expected a string or a number but received nothing');
     }
-    return;
-  }
-
-  if (readOnlyArrayHasStringMember(LOG_LEVEL_CLI_FLAGS, normalizedArg)) {
+  } else if (readOnlyArrayHasStringMember(LOG_LEVEL_CLI_FLAGS, normalizedArg)) {
     if (typeof value === 'string') {
       if (isLogLevel(value)) {
         flags[normalizedArg] = value;
@@ -321,7 +307,6 @@ const setCLIArg = (flags: ConfigFlags, rawArg: string, normalizedArg: string, va
     } else {
       throwCLIParsingError(rawArg, 'expected to receive a valid log level but received nothing');
     }
-    return;
   }
 };
 
@@ -347,9 +332,9 @@ const CLI_ARG_STRING_REGEX = /[^\d\.Ee\+\-]+/g;
 export const Empty = Symbol('Empty');
 
 /**
- * The result of trying to parse a CLI arg. `ArgValue` wraps up an argument if
- * present, while `Empty` indicates that nothing was matched or that the input
- * was malformed.
+ * The result of trying to parse a CLI arg. This will be a `string` if a
+ * well-formed value is present, or `Empty` to indicate that nothing was matched
+ * or that the input was malformed.
  */
 type CLIValueResult = string | typeof Empty;
 
@@ -377,6 +362,7 @@ const parseCLIValue = (args: string[]): CLIValueResult => {
     // until later on.
     const value = args.shift();
     if (typeof value === 'string') {
+      // this `if { }` block is just to keep TS happy :/
       return value;
     }
   }
@@ -434,7 +420,8 @@ const isLogLevel = (maybeLogLevel: string): maybeLogLevel is LogLevel =>
   readOnlyArrayHasStringMember(LOG_LEVELS, maybeLogLevel);
 
 /**
- * A little helper for constructing and throwing an error message with info about what went wrong
+ * A little helper for constructing and throwing an error message with info
+ * about what went wrong
  *
  * @param flag the flag which encountered the error
  * @param message a message specific to the error which was encountered
@@ -447,7 +434,7 @@ const throwCLIParsingError = (flag: string, message: string) => {
  * Throw a specific error for the situation where we ran into an issue parsing
  * a number.
  *
- * @param flag the flag for which we encounted the issue
+ * @param flag the flag for which we encountered the issue
  * @param value what we were trying to parse
  */
 const throwNumberParsingError = (flag: string, value: string) => {
@@ -456,11 +443,12 @@ const throwNumberParsingError = (flag: string, value: string) => {
 
 /**
  * A little helper to 'dereference' a flag alias, which if you squint a little
- * you can think of like a pointer to a full flag name. This 'c' is like a
+ * you can think of like a pointer to a full flag name. Thus 'c' is like a
  * pointer to 'config', so here we're doing something like `*c`. Of course, this
  * being JS, this is just a metaphor!
  *
- * If no 'dereference' is found for the possible alias we just return the passed string unmodified.
+ * If no 'dereference' is found for the possible alias we just return the
+ * passed string unmodified.
  *
  * @param maybeAlias a string which _could_ be an alias to a full flag name
  * @returns the full aliased flag name, if found, or the passed string if not