@@ -4,6 +4,10 @@ open System
 open FsCheck
 open FsCheck.NUnit
 open Paket
+open TestHelpers
+
+let nl = Environment.NewLine
+let linesToString s = String.concat nl s
 
 let source = Gen.constant "source https://nuget.org/api/v2"
 
@@ -15,19 +19,53 @@ let gist = Gen.constant "gist Thorium/1972349 timestamp.fs"
 
 let http = Gen.constant "http http://www.fssnip.net/1n decrypt.fs"
 
-let depLine = Gen.oneof [source; nuget; github; gist; http]
+let empty = Gen.constant ""
+
+let line = Gen.oneof [source; nuget; github; gist; http; empty]
+
+let slashComment = Gen.constant "//comment"
+let lineWComment = 
+    let line = Gen.oneof [source; nuget; empty]
+    (line, slashComment)
+    ||> Gen.map2 (fun l c -> l + " " + c)
+
+let hashComment = Gen.constant "#comment"
+let comment = Gen.oneof [slashComment; hashComment]
+
+let depLine = Gen.frequency [80, line; 10, lineWComment; 10, comment]
+
+let globalOpts = 
+    Gen.elements 
+        [ "references: strict"; "framework: net35, net40"; "content: none"; "import_targets: false"; "copy_local: false" ]
+    |> Gen.arrayOf
+    |> Gen.map (Seq.distinct >> Array.ofSeq)
+
+let generator = 
+    (Gen.arrayOf depLine, globalOpts)
+    ||> Gen.map2 (fun lines globalOpts -> Array.append globalOpts lines)
+    |> Gen.map linesToString
+
+let shrinker s =
+    let lines = s |> toLines
+    seq { 
+        for i in [0 .. lines.Length - 1] do
+            yield seq { 
+                for j in [0 .. lines.Length - 1] do
+                    if i <> j then yield lines.[j] }
+                |> linesToString}
 
 type DFFileGenerator =
     static member StringArray() = 
-        {new Arbitrary<string[]>() with
-            override x.Generator = Gen.arrayOf depLine
-            override x.Shrinker t = Seq.empty }
+        {new Arbitrary<string>() with
+            override x.Generator = generator
+            override x.Shrinker t = shrinker t }
 
 let _ = PropertyAttribute(Verbose = true)
 
 [<Property(
     Arbitrary = [|typeof<DFFileGenerator>|],
     Verbose = true)>]
-let ``round trip`` (lines : string[]) =
+let ``round trip`` (contents : string) =
+    let lines = toLines contents
     let df = DependenciesFile(DependenciesFileParser.parseDependenciesFile "dummy" lines)
     df.ToString() = String.concat Environment.NewLine lines