[gjs: 4/9] console: --jsversion shell option

[Cosimo Cecchi <cosimoc src gnome org>]

commit 5ad5b777f933ecfeeb659b2a9b66aed646394b63
Author: Philip Chimento <philip endlessm com>
Date:   Tue Nov 21 12:44:13 2017 -0800

    console: --jsversion shell option
    
    This adds a --jsversion command line option that prints whatever
    SpiderMonkey provides as its version. Also adds public API that does the
    same, gjs_get_js_version(), in case an embedding program such as GNOME
    Shell would want to print the version as well.

 gjs/console.cpp                            |  9 +++++++++
 gjs/context.cpp                            | 13 +++++++++++++
 gjs/context.h                              |  3 +++
 installed-tests/scripts/testCommandLine.sh | 26 ++++++++++++++------------
 4 files changed, 39 insertions(+), 12 deletions(-)
---
diff --git a/gjs/console.cpp b/gjs/console.cpp
index 9e8deec1..4c997227 100644
--- a/gjs/console.cpp
+++ b/gjs/console.cpp
@@ -36,6 +36,7 @@ static char *coverage_output_path = NULL;
 static char *profile_output_path = nullptr;
 static char *command = NULL;
 static gboolean print_version = false;
+static gboolean print_js_version = false;
 static bool enable_profiler = false;
 
 static gboolean parse_profile_arg(const char *, const char *, void *, GError **);
@@ -43,6 +44,8 @@ static gboolean parse_profile_arg(const char *, const char *, void *, GError **)
 /* Keep in sync with entries in check_script_args_for_stray_gjs_args() */
 static GOptionEntry entries[] = {
     { "version", 0, 0, G_OPTION_ARG_NONE, &print_version, "Print GJS version and exit" },
+    { "jsversion", 0, 0, G_OPTION_ARG_NONE, &print_js_version,
+        "Print version of the JS engine and exit" },
     { "command", 'c', 0, G_OPTION_ARG_STRING, &command, "Program passed in as a string", "COMMAND" },
     { "coverage-prefix", 'C', 0, G_OPTION_ARG_STRING_ARRAY, &coverage_prefixes, "Add the prefix PREFIX to 
the list of files to generate coverage info for", "PREFIX" },
     { "coverage-output", 0, 0, G_OPTION_ARG_STRING, &coverage_output_path, "Write coverage output to a 
directory DIR. This option is mandatory when using --coverage-path", "DIR", },
@@ -244,6 +247,7 @@ main(int argc, char **argv)
     coverage_output_path = NULL;
     command = NULL;
     print_version = false;
+    print_js_version = false;
     g_option_context_set_ignore_unknown_options(context, false);
     g_option_context_set_help_enabled(context, true);
     if (!g_option_context_parse_strv(context, &gjs_argv, &error))
@@ -256,6 +260,11 @@ main(int argc, char **argv)
         exit(0);
     }
 
+    if (print_js_version) {
+        g_print("%s\n", gjs_get_js_version());
+        exit(0);
+    }
+
     gjs_argc = g_strv_length(gjs_argv);
     if (command != NULL) {
         script = command;
diff --git a/gjs/context.cpp b/gjs/context.cpp
index e66a9f82..ff0b2097 100644
--- a/gjs/context.cpp
+++ b/gjs/context.cpp
@@ -1077,3 +1077,16 @@ gjs_context_get_profiler(GjsContext *self)
 {
     return self->profiler;
 }
+
+/**
+ * gjs_get_js_version:
+ *
+ * Returns the underlying version of the JS engine.
+ *
+ * Returns: a string
+ */
+const char *
+gjs_get_js_version(void)
+{
+    return JS_GetImplementationVersion();
+}
diff --git a/gjs/context.h b/gjs/context.h
index 8a2df292..5dfa3497 100644
--- a/gjs/context.h
+++ b/gjs/context.h
@@ -102,6 +102,9 @@ bool gjs_profiler_chain_signal(GjsContext *context,
 GJS_EXPORT
 void            gjs_dumpstack                     (void);
 
+GJS_EXPORT
+const char *gjs_get_js_version(void);
+
 G_END_DECLS
 
 #endif  /* __GJS_CONTEXT_H__ */
diff --git a/installed-tests/scripts/testCommandLine.sh b/installed-tests/scripts/testCommandLine.sh
index 040eb04f..a3d8738c 100755
--- a/installed-tests/scripts/testCommandLine.sh
+++ b/installed-tests/scripts/testCommandLine.sh
@@ -159,18 +159,20 @@ $gjs -c 'imports.system.exit(0)' --profile=foo 2>&1 | grep -q 'Gjs-WARNING.*--pr
 report "--profile after script should succeed but give a warning"
 rm -rf foo
 
-# --version works
-$gjs --version >/dev/null
-report "--version should work"
-test -n "$($gjs --version)"
-report "--version should print something"
-
-# --version after a script goes to the script
-script='if(ARGV[0] !== "--version") imports.system.exit(1)'
-$gjs -c "$script" --version
-report "--version after -c should be passed to script"
-test -z "$($gjs -c "$script" --version)"
-report "--version after -c should not print anything"
+for version_arg in --version --jsversion; do
+    # --version and --jsversion work
+    $gjs $version_arg >/dev/null
+    report "$version_arg should work"
+    test -n "$($gjs $version_arg)"
+    report "$version_arg should print something"
+
+    # --version and --jsversion after a script go to the script
+    script="if(ARGV[0] !== '$version_arg') imports.system.exit(1)"
+    $gjs -c "$script" $version_arg
+    report "$version_arg after -c should be passed to script"
+    test -z "$($gjs -c "$script" $version_arg)"
+    report "$version_arg after -c should not print anything"
+done
 
 # --profile
 rm -f gjs-*.syscap foo.syscap