Add support for determining name of script #14109

Note that PROGRAM_FILE was chosen as the name for this variable as it
matches the help for the Julia CLI.

Author: omus

NEWS.md

@@ -173,6 +173,8 @@ New language features
 
   * `@__LINE__` special macro now available to reflect invocation source line number ([#12727]).
 
+  * `PROGRAM_FILE` global is now available for determining the name of the running script ([#14114]).
+
 Language changes
 ----------------
 
@@ -1768,3 +1770,4 @@ Too numerous to mention.
 [#14413]: https://github.com/JuliaLang/julia/issues/14413
 [#14424]: https://github.com/JuliaLang/julia/issues/14424
 [#14759]: https://github.com/JuliaLang/julia/issues/14759
+[#14114]: https://github.com/JuliaLang/julia/issues/14114

base/client.jl

@@ -177,10 +177,9 @@ end
 # try to include() a file, ignoring if not found
 try_include(path::AbstractString) = isfile(path) && include(path)
 
-function process_options(opts::JLOptions, args::Vector{UTF8String})
-    if !isempty(args)
-        arg = first(args)
-        idxs = find(x -> x == "--", args)
+function process_options(opts::JLOptions)
+    if !isempty(ARGS)
+        idxs = find(x -> x == "--", ARGS)
         if length(idxs) > 1
             println(STDERR, "julia: redundant option terminator `--`")
             exit(1)
@@ -234,15 +233,15 @@ function process_options(opts::JLOptions, args::Vector{UTF8String})
             eval(Main, parse_input_line(bytestring(opts.postboot)))
         end
         # load file
-        if !isempty(args) && !isempty(args[1])
+        if !isempty(ARGS) && !isempty(ARGS[1])
             # program
             repl = false
             # remove filename from ARGS
-            shift!(ARGS)
+            global PROGRAM_FILE = UTF8String(shift!(ARGS))
             if !is_interactive
                 ccall(:jl_exit_on_sigint, Void, (Cint,), 1)
             end
-            include(args[1])
+            include(PROGRAM_FILE)
         end
         break
     end
@@ -298,7 +297,7 @@ function _start()
     append!(ARGS, Core.ARGS)
     opts = JLOptions()
     try
-        (quiet,repl,startup,color_set,history_file) = process_options(opts,copy(ARGS))
+        (quiet,repl,startup,color_set,history_file) = process_options(opts)
 
         local term
         global active_repl

base/docs/helpdb/Base.jl

@@ -8368,8 +8368,9 @@ graphemes
 """
     @__FILE__ -> AbstractString
 
-`@__FILE__` expands to a string with the absolute path and file name of the script being
-run. Returns `nothing` if run from a REPL or an empty string if evaluated by `julia -e <expr>`.
+`@__FILE__` expands to a string with the absolute file path of the file containing the
+macro. Returns `nothing` if run from a REPL or an empty string if evaluated by
+`julia -e <expr>`. Alternatively see [`PROGRAM_FILE`](:data:`PROGRAM_FILE`).
 """
 :@__FILE__
 

base/exports.jl

@@ -180,6 +180,7 @@ export
     JULIA_HOME,
     LOAD_PATH,
     OS_NAME,
+    PROGRAM_FILE,
     STDERR,
     STDIN,
     STDOUT,

base/initdefs.jl

@@ -2,6 +2,7 @@
 
 ## initdefs.jl - initialization and runtime management definitions
 
+PROGRAM_FILE = UTF8String("")
 const ARGS = UTF8String[]
 
 exit(n) = ccall(:jl_exit, Void, (Int32,), n)

doc/manual/getting-started.rst

@@ -51,19 +51,22 @@ argument to the julia command::
 
 As the example implies, the following command-line arguments to julia
 are taken as command-line arguments to the program ``script.jl``, passed
-in the global constant ``ARGS``. ``ARGS`` is also set when script code
-is given using the ``-e`` option on the command line (see the ``julia``
-help output below). For example, to just print the arguments given to a
-script, you could do this::
+in the global constant ``ARGS``. The name of the script itself is passed
+in as the global ``PROGRAM_FILE``. Note that ``ARGS`` is also set when script
+code is given using the ``-e`` option on the command line (see the ``julia``
+help output below) but ``PROGRAM_FILE`` will be empty. For example, to just
+print the arguments given to a script, you could do this::
+
+    $ julia -e 'println(PROGRAM_FILE); for x in ARGS; println(x); end' foo bar
 
-    $ julia -e 'for x in ARGS; println(x); end' foo bar
     foo
     bar
 
 Or you could put that code into a script and run it::
 
-    $ echo 'for x in ARGS; println(x); end' > script.jl
+    $ echo 'println(PROGRAM_FILE); for x in ARGS; println(x); end' > script.jl
     $ julia script.jl foo bar
+    script.jl
     foo
     bar
 

doc/stdlib/constants.rst

@@ -14,6 +14,11 @@ Constants
    A symbol representing the name of the operating system. Possible values
    are ``:Linux``, ``:Darwin`` (OS X), or ``:Windows``.
 
+.. data:: PROGRAM_FILE
+
+   A string containing the script name passed to Julia from the command line. Note that the
+   script name remains unchanged from within included files. Alternatively see :data:`@__FILE__`.
+
 .. data:: ARGS
 
    An array of the command line arguments passed to Julia, as strings.

doc/stdlib/file.rst

@@ -337,7 +337,7 @@
 
    .. Docstring generated from Julia source
 
-   ``@__FILE__`` expands to a string with the absolute path and file name of the script being run. Returns ``nothing`` if run from a REPL or an empty string if evaluated by ``julia -e <expr>``\ .
+   ``@__FILE__`` expands to a string with the absolute file path of the file containing the macro. Returns ``nothing`` if run from a REPL or an empty string if evaluated by ``julia -e <expr>``. Alternatively see :data:`PROGRAM_FILE`.
 
 .. function:: @__LINE__ -> Int
 

test/cmdlineargs.jl

@@ -204,24 +204,49 @@ let exename = `$(joinpath(JULIA_HOME, Base.julia_exename())) --precompiled=yes`
     # --worker takes default / custom as arugment (default/custom arguments tested in test/parallel.jl, test/examples.jl)
     @test !success(`$exename --worker=true`)
 
+    escape(str) = replace(str, "\\", "\\\\")
+
     # test passing arguments
     let testfile = tempname()
         try
-            # write a julia source file that just prints ARGS to STDOUT and exits
+            # write a julia source file that just prints ARGS to STDOUT
             write(testfile, """
                 println(ARGS)
-                exit(0)
             """)
-            @test readchomp(`$exename $testfile foo -bar --baz`) ==  "UTF8String[\"foo\",\"-bar\",\"--baz\"]"
-            @test readchomp(`$exename $testfile -- foo -bar --baz`) ==  "UTF8String[\"foo\",\"-bar\",\"--baz\"]"
-            @test readchomp(`$exename -L $testfile -- foo -bar --baz`) ==  "UTF8String[\"foo\",\"-bar\",\"--baz\"]"
+            @test readchomp(`$exename $testfile foo -bar --baz`) == "UTF8String[\"foo\",\"-bar\",\"--baz\"]"
+            @test readchomp(`$exename $testfile -- foo -bar --baz`) == "UTF8String[\"foo\",\"-bar\",\"--baz\"]"
+            @test readchomp(`$exename -L $testfile -e 'exit(0)' -- foo -bar --baz`) == "UTF8String[\"foo\",\"-bar\",\"--baz\"]"
+            @test split(readchomp(`$exename -L $testfile $testfile`), '\n') == ["UTF8String[\"$(escape(testfile))\"]", "UTF8String[]"]
             @test !success(`$exename --foo $testfile`)
-            @test !success(`$exename -L $testfile -- foo -bar -- baz`)
+            @test !success(`$exename -L $testfile -e 'exit(0)' -- foo -bar -- baz`)
         finally
             rm(testfile)
         end
     end
 
+    # test the script name
+    let a = tempname(), b = tempname()
+        try
+            write(a, """
+                println(@__FILE__)
+                println(PROGRAM_FILE)
+                println(length(ARGS))
+                include(\"$(escape(b))\")
+            """)
+            write(b, """
+                println(@__FILE__)
+                println(PROGRAM_FILE)
+                println(length(ARGS))
+            """)
+            @test split(readchomp(`$exename $a`), '\n') == ["$a", "$a", "0", "$b", "$a", "0"]
+            @test split(readchomp(`$exename -L $b -e 'exit(0)'`), '\n') == ["$(realpath(b))", "", "0"]
+            @test split(readchomp(`$exename -L $b $a`), '\n') == ["$(realpath(b))", "", "1", "$a", "$a", "0", "$b", "$a", "0"]
+        finally
+            rm(a)
+            rm(b)
+        end
+    end
+
     # issue #10562
     @test readchomp(`$exename -e 'println(ARGS);' ''`) == "UTF8String[\"\"]"