Add #version;; directive to F# Interactive

Prints version, .NET runtime, and OS/architecture info on demand,
useful for debugging and bug reporting when the startup banner has
scrolled away. Closes #13307.

Author: bbatsov

docs/release-notes/.FSharp.Compiler.Service/10.0.300.md

@@ -2,6 +2,8 @@
 
 ### Added
 
+* Add `#version;;` directive to F# Interactive to display version and environment information. ([Issue #13307](https://github.com/dotnet/fsharp/issues/13307), [PR #19332](https://github.com/dotnet/fsharp/pull/19332))
+
 ### Changed
 
 ### Breaking Changes

src/Compiler/Interactive/FSIstrings.txt

@@ -35,6 +35,7 @@ fsiIntroTextHashhelpInfo,"Display help"
 fsiIntroTextHashhelpdocInfo,"Display documentation for an identifier, e.g. #help \"List.map\";;"
 fsiIntroTextHashquitInfo,"Exit"
 fsiIntroTextHashclearInfo,"Clear screen"
+fsiIntroTextHashversionInfo,"Display F# Interactive version and environment information"
 fsiIntroTextHeader2commandLine,"  F# Interactive command line options:"
 fsiIntroTextHeader3,"      See '%s' for options"
 fsiLoadingFilesPrefixText,"Loading"

src/Compiler/Interactive/fsi.fs

@@ -1263,6 +1263,16 @@ type internal FsiCommandLineOptions(fsi: FsiEvaluationSessionHostConfig, argv: s
         fsiConsoleOutput.uprintfnn "%s" (FSComp.SR.optsCopyright ())
         fsiConsoleOutput.uprintfn "%s" (FSIstrings.SR.fsiBanner3 ())
 
+    member _.ShowVersion() =
+        fsiConsoleOutput.uprintnfn "%s" tcConfigB.productNameForBannerText
+
+        fsiConsoleOutput.uprintnfn ".NET: %s" System.Runtime.InteropServices.RuntimeInformation.FrameworkDescription
+
+        fsiConsoleOutput.uprintnfn
+            "OS: %s (%O)"
+            System.Runtime.InteropServices.RuntimeInformation.OSDescription
+            System.Runtime.InteropServices.RuntimeInformation.ProcessArchitecture
+
     member _.ShowHelp(m) =
         let helpLine = sprintf "%s --help" executableFileNameWithoutExtension.Value
 
@@ -1294,6 +1304,11 @@ type internal FsiCommandLineOptions(fsi: FsiEvaluationSessionHostConfig, argv: s
                 fsiConsoleOutput.uprintfn "%s" msg
 
         fsiConsoleOutput.uprintfn """    #clear;;                                      // %s""" (FSIstrings.SR.fsiIntroTextHashclearInfo ())
+
+        fsiConsoleOutput.uprintfn
+            """    #version;;                                    // %s"""
+            (FSIstrings.SR.fsiIntroTextHashversionInfo ())
+
         fsiConsoleOutput.uprintfn """    #quit;;                                       // %s""" (FSIstrings.SR.fsiIntroTextHashquitInfo ())
         fsiConsoleOutput.uprintfn ""
         fsiConsoleOutput.uprintfnn "%s" (FSIstrings.SR.fsiIntroTextHeader2commandLine ())
@@ -3885,6 +3900,10 @@ type FsiInteractionProcessor
             fsiOptions.ClearScreen()
             istate, Completed None
 
+        | ParsedHashDirective("version", [], _) ->
+            fsiOptions.ShowVersion()
+            istate, Completed None
+
         | ParsedHashDirective(("q" | "quit"), [], _) -> fsiInterruptController.Exit()
 
         | ParsedHashDirective("help", hashArguments, m) ->