Revert "rust: validate existence of library source"

Revert submission 1391076

Reason for revert: Broken downstream Darwin build (b/162975597)
Reverted Changes:
I275f04639:rust: handle modules with same crate_name
Ie736d7ebb:rust: validate existence of library source

Change-Id: I1732d50a08546864f17cd826c8af574c1064c670
diff --git a/rust/project_json_test.go b/rust/project_json_test.go
index 89ba8d3..6786e72 100644
--- a/rust/project_json_test.go
+++ b/rust/project_json_test.go
@@ -15,7 +15,6 @@
 package rust
 
 import (
-	"encoding/json"
 	"io/ioutil"
 	"path/filepath"
 	"testing"
@@ -24,12 +23,20 @@
 	"android/soong/cc"
 )
 
-// testProjectJson run the generation of rust-project.json. It returns the raw
-// content of the generated file.
-func testProjectJson(t *testing.T, bp string, fs map[string][]byte) []byte {
+func TestProjectJson(t *testing.T) {
+	bp := `rust_library {
+		  name: "liba",
+		  srcs: ["src/lib.rs"],
+		  crate_name: "a"
+		}` + GatherRequiredDepsForTest()
+	env := map[string]string{"SOONG_GEN_RUST_PROJECT": "1"}
+	fs := map[string][]byte{
+		"foo.rs":     nil,
+		"src/lib.rs": nil,
+	}
+
 	cc.GatherRequiredFilesForTest(fs)
 
-	env := map[string]string{"SOONG_GEN_RUST_PROJECT": "1"}
 	config := android.TestArchConfig(buildDir, env, bp, fs)
 	ctx := CreateTestContext()
 	ctx.Register(config)
@@ -41,79 +48,8 @@
 	// The JSON file is generated via WriteFileToOutputDir. Therefore, it
 	// won't appear in the Output of the TestingSingleton. Manually verify
 	// it exists.
-	content, err := ioutil.ReadFile(filepath.Join(buildDir, rustProjectJsonFileName))
+	_, err := ioutil.ReadFile(filepath.Join(buildDir, "rust-project.json"))
 	if err != nil {
 		t.Errorf("rust-project.json has not been generated")
 	}
-	return content
-}
-
-// validateJsonCrates validates that content follows the basic structure of
-// rust-project.json. It returns the crates attribute if the validation
-// succeeded.
-// It uses an empty interface instead of relying on a defined structure to
-// avoid a strong dependency on our implementation.
-func validateJsonCrates(t *testing.T, rawContent []byte) []interface{} {
-	var content interface{}
-	err := json.Unmarshal(rawContent, &content)
-	if err != nil {
-		t.Errorf("Unable to parse the rust-project.json as JSON: %v", err)
-	}
-	root, ok := content.(map[string]interface{})
-	if !ok {
-		t.Errorf("Unexpected JSON format: %v", content)
-	}
-	if _, ok = root["crates"]; !ok {
-		t.Errorf("No crates attribute in rust-project.json: %v", root)
-	}
-	crates, ok := root["crates"].([]interface{})
-	if !ok {
-		t.Errorf("Unexpected crates format: %v", root["crates"])
-	}
-	return crates
-}
-
-func TestProjectJsonDep(t *testing.T) {
-	bp := `
-	rust_library {
-		name: "liba",
-		srcs: ["a/src/lib.rs"],
-		crate_name: "a"
-	}
-	rust_library {
-		name: "libb",
-		srcs: ["b/src/lib.rs"],
-		crate_name: "b",
-		rlibs: ["liba"],
-	}
-	` + GatherRequiredDepsForTest()
-	fs := map[string][]byte{
-		"a/src/lib.rs": nil,
-		"b/src/lib.rs": nil,
-	}
-	jsonContent := testProjectJson(t, bp, fs)
-	validateJsonCrates(t, jsonContent)
-}
-
-func TestProjectJsonBindGen(t *testing.T) {
-	bp := `
-	rust_library {
-		name: "liba",
-		srcs: ["src/lib.rs"],
-		rlibs: ["libbindings"],
-		crate_name: "a"
-	}
-	rust_bindgen {
-		name: "libbindings",
-		crate_name: "bindings",
-		source_stem: "bindings",
-		host_supported: true,
-		wrapper_src: "src/any.h",
-	}
-	` + GatherRequiredDepsForTest()
-	fs := map[string][]byte{
-		"src/lib.rs": nil,
-	}
-	jsonContent := testProjectJson(t, bp, fs)
-	validateJsonCrates(t, jsonContent)
 }