Export OUT_DIR variable to rust-project.json

This variable is required by rust-analyzer to correctly process crates
that uses the include!(concat!(env!("OUT_DIR"), ...)) pattern.

Adds an initialize method to baseCompiler to save the computed path for
this directory. It is not possible to use the BeginMutator as the
BaseModuleContext does not contain enough information to use
PathForModuleOut.

Bug: 175004835
Test: SOONG_GEN_RUST_PROJECT=1 m nothing; inspect rust-project.json
Change-Id: If47b3832d3cca5712ae87773c174a61f5ee27bf8

1 files changed, 11 insertions, 2 deletions

diff --git a/rust/project_json_test.go b/rust/project_json_test.go
index ba66215c5..289bcb81d 100644
--- a/rust/project_json_test.go
+++ b/rust/project_json_test.go
@@ -190,8 +190,8 @@ func TestProjectJsonBindGen(t *testing.T) {
 				}
 			}
 		}
-		// Check that liba depends on libbindings1
 		if strings.Contains(rootModule, "d/src/lib.rs") {
+			// Check that libd depends on libbindings1
 			found := false
 			for _, depName := range validateDependencies(t, crate) {
 				if depName == "bindings1" {
@@ -200,8 +200,17 @@ func TestProjectJsonBindGen(t *testing.T) {
 				}
 			}
 			if !found {
-				t.Errorf("liba does not depend on libbindings1: %v", crate)
+				t.Errorf("libd does not depend on libbindings1: %v", crate)
 			}
+			// Check that OUT_DIR is populated.
+			env, ok := crate["env"].(map[string]interface{})
+			if !ok {
+				t.Errorf("libd does not have its environment variables set: %v", crate)
+			}
+			if _, ok = env["OUT_DIR"]; !ok {
+				t.Errorf("libd does not have its OUT_DIR set: %v", env)
+			}
+
 		}
 	}
 }