[gnome-builder/wip/gtk4-port] libide/foundry: add push_error api for run command

[Christian Hergert <chergert src gnome org>]

commit 836b441a13c60e2dbd56113336f4e31dc8d94430
Author: Christian Hergert <chergert redhat com>
Date:   Mon Jun 27 14:32:15 2022 -0700

    libide/foundry: add push_error api for run command
    
    This is convenience API so that if you don't need a handler but still want
    to propagate an error, which will block the final creation of a launcher,
    you can do so synchronously.
    
    When flattening layers, the error will propagate and stop further creation
    of the subprocess launcher.

 src/libide/foundry/ide-run-context.c | 45 ++++++++++++++++++++++++++++++++++++
 src/libide/foundry/ide-run-context.h |  3 +++
 2 files changed, 48 insertions(+)
---
diff --git a/src/libide/foundry/ide-run-context.c b/src/libide/foundry/ide-run-context.c
index 58ed61ce3..9c47ce5d4 100644
--- a/src/libide/foundry/ide-run-context.c
+++ b/src/libide/foundry/ide-run-context.c
@@ -298,6 +298,51 @@ ide_run_context_push_host (IdeRunContext *self)
                           NULL);
 }
 
+static gboolean
+ide_run_context_error_handler (IdeRunContext       *self,
+                               const char * const  *argv,
+                               const char * const  *env,
+                               const char          *cwd,
+                               IdeUnixFDMap        *unix_fd_map,
+                               gpointer             user_data,
+                               GError             **error)
+{
+  const GError *local_error = user_data;
+
+  g_assert (IDE_IS_RUN_CONTEXT (self));
+  g_assert (IDE_IS_UNIX_FD_MAP (unix_fd_map));
+  g_assert (local_error != NULL);
+
+  if (error != NULL)
+    *error = g_error_copy (local_error);
+
+  return FALSE;
+}
+
+/**
+ * ide_run_context_push_error:
+ * @self: a #IdeRunContext
+ * @error: (transfer full) (in): a #GError
+ *
+ * Pushes a new layer that will always fail with @error.
+ *
+ * This is useful if you have an error when attempting to build
+ * a run command, but need it to deliver the error when attempting
+ * to create a subprocess launcher.
+ */
+void
+ide_run_context_push_error (IdeRunContext *self,
+                            GError        *error)
+{
+  g_return_if_fail (IDE_IS_RUN_CONTEXT (self));
+  g_return_if_fail (error != NULL);
+
+  ide_run_context_push (self,
+                        ide_run_context_error_handler,
+                        error,
+                        (GDestroyNotify)g_error_free);
+}
+
 static gboolean
 next_variable (const char *str,
                guint      *cursor,
diff --git a/src/libide/foundry/ide-run-context.h b/src/libide/foundry/ide-run-context.h
index 9171f05f4..f34105114 100644
--- a/src/libide/foundry/ide-run-context.h
+++ b/src/libide/foundry/ide-run-context.h
@@ -56,6 +56,9 @@ void                   ide_run_context_push                    (IdeRunContext
                                                                 gpointer               handler_data,
                                                                 GDestroyNotify         handler_data_destroy);
 IDE_AVAILABLE_IN_ALL
+void                   ide_run_context_push_error              (IdeRunContext         *self,
+                                                                GError                *error);
+IDE_AVAILABLE_IN_ALL
 void                   ide_run_context_push_host               (IdeRunContext         *self);
 IDE_AVAILABLE_IN_ALL
 void                   ide_run_context_push_expansion          (IdeRunContext         *self,