Use custom type for file parts

Author: codeconscious

src/UniqueFileGenerator.Console/Io.fs

@@ -90,17 +90,16 @@ module Io =
 
     let generateFiles (args: Args) =
         let count, prefix, baseLength, extension, outputDir, size, delay =
-            (args.FileCount,
-             args.Options.Prefix,
-             args.Options.NameBaseLength,
-             args.Options.Extension,
-             args.Options.OutputDirectory,
-             args.Options.Size,
-             args.Options.Delay)
+            args.FileCount,
+            args.Options.Prefix,
+            args.Options.NameBaseLength,
+            args.Options.Extension,
+            args.Options.OutputDirectory,
+            args.Options.Size,
+            args.Options.Delay
 
         let updateFileName baseName =
-            baseName
-            |> toFileName prefix extension
+            toFileName { Prefix = prefix; BaseName = baseName; Extension = extension }
 
         let sleep (ms: int) x =
             Thread.Sleep ms
@@ -114,5 +113,5 @@ module Io =
             |> printResult
 
         generateMultiple baseLength count
-            |> Array.map updateFileName
-            |> Array.iter writeFile
+        |> Array.map updateFileName
+        |> Array.iter writeFile

src/UniqueFileGenerator.Console/StringGeneration.fs

@@ -3,6 +3,8 @@ namespace UniqueFileGenerator.Console
 open System
 
 module StringGeneration =
+    type FileNameParts = { Prefix: string; BaseName: string; Extension: string; }
+
     let private charBank =
         [ 'A' .. 'Z' ] @ [ 'a' .. 'z' ] @ [ '0' .. '9' ]
         |> List.map string
@@ -17,14 +19,14 @@ module StringGeneration =
     let generateMultiple itemLength count : string array =
         Array.init count (fun _ -> generateSingle itemLength)
 
-    let toFileName (prefix: string) (extension: string) (baseName: string) : string =
+    let toFileName parts : string =
         let safeExtension =
-            match extension.Trim() with
+            match parts.Extension.Trim() with
             | ext when String.IsNullOrWhiteSpace ext -> String.Empty
             | ext when ext.StartsWith '.' -> ext
             | ext -> $".%s{ext}"
 
-        $"%s{prefix}%s{baseName}%s{safeExtension}"
+        $"%s{parts.Prefix.Trim()}%s{parts.BaseName}%s{safeExtension}"
 
     let generateFileContent sizeInBytes fallback : string =
         sizeInBytes

src/UniqueFileGenerator.Tests/StringGenerationTests.fs

@@ -50,8 +50,7 @@ module FileNames =
 
         let fileNames =
             generated
-            |> Array.map (fun x ->
-                x |> toFileName prefix extension)
+            |> Array.map (fun x -> toFileName { Prefix = prefix; BaseName = x; Extension = extension })
 
         Assert.Equal<string[]>(generated, fileNames)
 
@@ -63,8 +62,7 @@ module FileNames =
 
         let fileNames =
             generated
-            |> Array.map (fun x ->
-                x |> toFileName prefix extension)
+            |> Array.map (fun x -> toFileName { Prefix = prefix; BaseName = x; Extension = extension })
 
         Assert.True(fileNames |> Array.forall (fun x -> x.StartsWith prefix))
 
@@ -76,8 +74,7 @@ module FileNames =
 
         let fileNames =
             generated
-            |> Array.map (fun x ->
-                x |> toFileName prefix extension)
+            |> Array.map (fun x -> toFileName { Prefix = prefix; BaseName = x; Extension = extension })
 
         Assert.True(fileNames |> Array.forall (fun x -> x.EndsWith extension))
 
@@ -89,8 +86,7 @@ module FileNames =
 
         let fileNames =
             generated
-            |> Array.map (fun x ->
-                x |> toFileName prefix extension)
+            |> Array.map (fun x -> toFileName { Prefix = prefix; BaseName = x; Extension = extension })
 
         Assert.True(fileNames |> Array.forall (fun x -> x.StartsWith prefix))
         Assert.True(fileNames |> Array.forall (fun x -> x.EndsWith extension))