internal/imports: clean up dead code

Now that we're storing module information per-directory, we don't need
to pre-compute the need for a replace statement. And we never have the
package name in the place it used to be set.

Change-Id: I3b0845dc49f52f8c449840410dbb786fe903d29d
Reviewed-on: https://go-review.googlesource.com/c/tools/+/212861
Run-TryBot: Heschi Kreinick <heschi@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rebecca Stambler <rstambler@golang.org>

internal/imports/mod.go

@@ -488,14 +488,15 @@ func (r *ModuleResolver) canonicalize(info directoryPackageInfo) (*pkg, error) {
 			dirInMod := info.dir[len(mod.Dir)+len("/"):]
 			importPath = path.Join(mod.Path, filepath.ToSlash(dirInMod))
 		}
-	} else if info.needsReplace {
+	} else if !strings.HasPrefix(importPath, info.moduleName) {
+		// The module's name doesn't match the package's import path. It
+		// probably needs a replace directive we don't have.
 		return nil, fmt.Errorf("package in %q is not valid without a replace statement", info.dir)
 	}
 
 	res := &pkg{
 		importPathShort: importPath,
 		dir:             info.dir,
-		packageName:     info.packageName, // may not be populated if the caller didn't ask for it
 		relevance:       relevance,
 	}
 	// We may have discovered a package that has a different version
@@ -559,7 +560,6 @@ func (r *ModuleResolver) scanDirForPackage(root gopathwalk.Root, dir string) dir
 		dir:                    dir,
 		rootType:               root.Type,
 		nonCanonicalImportPath: importPath,
-		needsReplace:           false,
 		moduleDir:              modDir,
 		moduleName:             modName,
 	}
@@ -567,14 +567,6 @@ func (r *ModuleResolver) scanDirForPackage(root gopathwalk.Root, dir string) dir
 		// stdlib packages are always in scope, despite the confusing go.mod
 		return result
 	}
-	// Check that this package is not obviously impossible to import.
-	if !strings.HasPrefix(importPath, modName) {
-		// The module's declared path does not match
-		// its expected path. It probably needs a
-		// replace directive we don't have.
-		result.needsReplace = true
-	}
-
 	return result
 }
 

internal/imports/mod_cache.go

@@ -49,10 +49,6 @@ type directoryPackageInfo struct {
 	// nonCanonicalImportPath is the package's expected import path. It may
 	// not actually be importable at that path.
 	nonCanonicalImportPath string
-	// needsReplace is true if the nonCanonicalImportPath does not match the
-	// module's declared path, making it impossible to import without a
-	// replace directive.
-	needsReplace bool
 
 	// Module-related information.
 	moduleDir  string // The directory that is the module root of this dir.

internal/imports/mod_cache_test.go

@@ -68,7 +68,6 @@ func TestModCacheInfo(t *testing.T) {
 				status:                 directoryScanned,
 				dir:                    "mypackage",
 				nonCanonicalImportPath: "example.com/mypackage",
-				needsReplace:           false,
 			},
 		},
 		{
@@ -83,7 +82,6 @@ func TestModCacheInfo(t *testing.T) {
 			info: directoryPackageInfo{
 				dir:                    "mypackage/other",
 				nonCanonicalImportPath: "example.com/mypackage/other",
-				needsReplace:           false,
 			},
 		},
 	}