[gnome-builder] cargo: check $CARGO and ~/.cargo/bin/cargo

[Christian Hergert <chergert src gnome org>]

commit 2227dfac4d1b1a5585fd37ff15d8ff624b5e70c6
Author: Christian Hergert <chergert redhat com>
Date:   Sat Mar 18 03:45:25 2017 -0700

    cargo: check $CARGO and ~/.cargo/bin/cargo
    
    We might need to use an alternative cargo binary, so make that possible.

 plugins/cargo/cargo_plugin.py |   17 ++++++++++++++---
 1 files changed, 14 insertions(+), 3 deletions(-)
---
diff --git a/plugins/cargo/cargo_plugin.py b/plugins/cargo/cargo_plugin.py
index afe83ed..62bdd23 100644
--- a/plugins/cargo/cargo_plugin.py
+++ b/plugins/cargo/cargo_plugin.py
@@ -21,6 +21,7 @@
 
 import gi
 import threading
+import os
 
 gi.require_version('Ide', '1.0')
 
@@ -85,11 +86,21 @@ class CargoPipelineAddin(Ide.Object, Ide.BuildPipelineAddin):
         config = pipeline.get_configuration()
         system_type = config.get_device().get_system_type()
         builddir = pipeline.get_builddir()
+        runtime = config.get_runtime()
+
+        # We might need to use cargo from ~/.cargo/bin
+        cargo = _CARGO
+        if config.getenv('CARGO'):
+            cargo = config.getenv('CARGO')
+        elif not runtime.contains_program_in_path(_CARGO):
+            cargo_in_home = os.path.expanduser('~/.cargo/bin/cargo')
+            if os.path.exists(cargo_in_home):
+                cargo = cargo_in_home
 
         # Fetch dependencies so that we no longer need network access
         fetch_launcher = pipeline.create_launcher()
         fetch_launcher.setenv('CARGO_TARGET_DIR', builddir, True)
-        fetch_launcher.push_argv(_CARGO)
+        fetch_launcher.push_argv(cargo)
         fetch_launcher.push_argv('fetch')
         fetch_launcher.push_argv('--manifest-path')
         fetch_launcher.push_argv(cargo_toml)
@@ -98,7 +109,7 @@ class CargoPipelineAddin(Ide.Object, Ide.BuildPipelineAddin):
         # Fetch dependencies so that we no longer need network access
         build_launcher = pipeline.create_launcher()
         build_launcher.setenv('CARGO_TARGET_DIR', builddir, True)
-        build_launcher.push_argv(_CARGO)
+        build_launcher.push_argv(cargo)
         build_launcher.push_argv('build')
         build_launcher.push_argv('--manifest-path')
         build_launcher.push_argv(cargo_toml)
@@ -117,7 +128,7 @@ class CargoPipelineAddin(Ide.Object, Ide.BuildPipelineAddin):
 
         clean_launcher = pipeline.create_launcher()
         clean_launcher.setenv('CARGO_TARGET_DIR', builddir, True)
-        clean_launcher.push_argv(_CARGO)
+        clean_launcher.push_argv(cargo)
         clean_launcher.push_argv('clean')
         clean_launcher.push_argv('--manifest-path')
         clean_launcher.push_argv(cargo_toml)