Replace SNAPCRAFT_PART_INSTALL in the part attributes. (#841)

LP: #1628915

integration_tests/snaps/simple-cmake-replace/CMakeLists.txt

@@ -0,0 +1,5 @@
+cmake_minimum_required(VERSION 3.2)
+project(simple-cmake-replace C)
+add_definitions(-DPART_INSTALL=${PART_INSTALL})
+add_executable(simple-cmake-replace test.c)
+install(TARGETS simple-cmake-replace RUNTIME DESTINATION bin)

integration_tests/snaps/simple-cmake-replace/snapcraft.yaml

@@ -0,0 +1,14 @@
+name: test-package
+version: 0.1
+summary: one line summary
+description: a longer description
+icon: icon.png
+confinement: strict
+
+build-packages: [gcc, libc6-dev]
+
+parts:
+  cmake-project:
+    plugin: cmake
+    configflags: ['-DPART_INSTALL="$SNAPCRAFT_PART_INSTALL"']
+    source: .

integration_tests/snaps/simple-cmake-replace/test.c

@@ -0,0 +1,5 @@
+#include <stdio.h>
+
+int main() {
+    printf("When I was built I was installed to %s\n", PART_INSTALL);
+}

integration_tests/test_environment.py

@@ -15,6 +15,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import os
+import subprocess
 
 from testtools.matchers import FileContains
 
@@ -56,3 +57,17 @@ def test_snapcraft_stage_env_replacement(self):
         project_dir = 'stage_env'
 
         self.run_snapcraft('stage', project_dir)
+
+    def test_stage_cmake_plugin_with_replace(self):
+        """Replace SNAPCRAFT_PART_INSTALL in the part's attributes"""
+        project_dir = 'simple-cmake-replace'
+        self.run_snapcraft('stage', project_dir)
+
+        binary_output = subprocess.check_output([
+            os.path.join('stage', 'bin', 'simple-cmake-replace')],
+            cwd=project_dir)
+        path = os.path.join(os.getcwd(), project_dir, 'parts',
+                            'cmake-project', 'install')
+        self.assertEqual(
+            "When I was built I was installed to {}\n".format(path),
+            binary_output.decode('utf-8'))

snapcraft/internal/lifecycle.py

@@ -35,6 +35,7 @@
     pluginhandler,
     repo,
 )
+from snapcraft.internal.project_loader import replace_attr
 
 
 logger = logging.getLogger(__name__)
@@ -106,6 +107,16 @@ def execute(step, project_options, part_names=None):
             'type': config.data.get('type', '')}
 
 
+def _replace_in_part(part):
+    for key, value in part.code.options.__dict__.items():
+        value = replace_attr(value, [
+            ('$SNAPCRAFT_PART_INSTALL', part.code.installdir),
+        ])
+        setattr(part.code.options, key, value)
+
+    return part
+
+
 class _Executor:
 
     def __init__(self, config, project_options):
@@ -181,6 +192,7 @@ def _run_step(self, step, part, part_names):
         common.env = self.parts_config.build_env_for_part(part)
         common.env.extend(self.config.project_env())
 
+        part = _replace_in_part(part)
         getattr(part, step)()
 
     def _create_meta(self, step, part_names):

snapcraft/tests/test_lifecycle.py

@@ -50,6 +50,25 @@ def make_snapcraft_yaml(self, parts, snap_type=''):
 
         super().make_snapcraft_yaml(yaml.format(parts=parts, type=snap_type))
 
+    def test__replace_in_parts(self):
+        class Options:
+            def __init__(self):
+                self.source = '$SNAPCRAFT_PART_INSTALL'
+
+        class Code:
+            def __init__(self):
+                self.options = Options()
+                self.installdir = '/tmp'
+
+        class Part:
+            def __init__(self):
+                self.code = Code()
+
+        part = Part()
+        new_part = lifecycle._replace_in_part(part)
+
+        self.assertEqual(part.code.installdir, new_part.code.options.source)
+
     def test_exception_when_dependency_is_required(self):
         self.make_snapcraft_yaml("""parts:
   part1: