[gnome-builder] subprocess: add helper to append to $PATH

[Christian Hergert <chergert src gnome org>]

commit bdc1895cc80b3b9066fe4fc46577ff2dd4fee51e
Author: Christian Hergert <chergert redhat com>
Date:   Tue Jan 16 00:42:35 2018 -0800

    subprocess: add helper to append to $PATH
    
    This is useful in situations where we need to getenv, append,
    setenv.

 src/libide/subprocess/ide-subprocess-launcher.c | 24 ++++++++++++++++++++++++
 src/libide/subprocess/ide-subprocess-launcher.h |  3 +++
 2 files changed, 27 insertions(+)
---
diff --git a/src/libide/subprocess/ide-subprocess-launcher.c b/src/libide/subprocess/ide-subprocess-launcher.c
index ee374bb0c..957305452 100644
--- a/src/libide/subprocess/ide-subprocess-launcher.c
+++ b/src/libide/subprocess/ide-subprocess-launcher.c
@@ -996,3 +996,27 @@ ide_subprocess_launcher_set_stdout_file_path (IdeSubprocessLauncher *self,
       priv->stdout_file_path = g_strdup (stdout_file_path);
     }
 }
+
+void
+ide_subprocess_launcher_append_path (IdeSubprocessLauncher *self,
+                                     const gchar           *path)
+{
+  const gchar *old_path;
+
+  g_return_if_fail (IDE_IS_SUBPROCESS_LAUNCHER (self));
+
+  if (path == NULL)
+    return;
+
+  old_path = ide_subprocess_launcher_getenv (self, "PATH");
+
+  if (old_path != NULL)
+    {
+      g_autofree gchar *new_path = g_strdup_printf ("%s:%s", old_path, path);
+      ide_subprocess_launcher_setenv (self, "PATH", new_path, TRUE);
+    }
+  else
+    {
+      ide_subprocess_launcher_setenv (self, "PATH", path, TRUE);
+    }
+}
diff --git a/src/libide/subprocess/ide-subprocess-launcher.h b/src/libide/subprocess/ide-subprocess-launcher.h
index 360774f27..ea580c2f2 100644
--- a/src/libide/subprocess/ide-subprocess-launcher.h
+++ b/src/libide/subprocess/ide-subprocess-launcher.h
@@ -66,6 +66,9 @@ gboolean               ide_subprocess_launcher_get_run_on_host     (IdeSubproces
 IDE_AVAILABLE_IN_ALL
 void                   ide_subprocess_launcher_set_run_on_host     (IdeSubprocessLauncher  *self,
                                                                     gboolean                run_on_host);
+IDE_AVAILABLE_IN_3_28
+void                   ide_subprocess_launcher_append_path         (IdeSubprocessLauncher  *self,
+                                                                    const gchar            *append_path);
 IDE_AVAILABLE_IN_ALL
 gboolean               ide_subprocess_launcher_get_clear_env       (IdeSubprocessLauncher  *self);
 IDE_AVAILABLE_IN_ALL