[DO NOT MERGE, need fix verification] manifest: skip ProjectRoot validation for alt source

gps/solver.go

@@ -399,6 +399,17 @@ func (e DeductionErrs) Error() string {
 
 // ValidateParams validates the solver parameters to ensure solving can be completed.
 func ValidateParams(params SolveParameters, sm SourceManager) error {
+	// Create a list of projects to skip project root deduction. This is
+	// required for projects with an alternate source.
+	altSrc := make(map[string]bool)
+	if params.Manifest != nil {
+		for proj, prop := range params.Manifest.DependencyConstraints() {
+			if prop.Source != "" {
+				altSrc[string(proj)] = true
+			}
+		}
+	}
+
 	// Ensure that all packages are deducible without issues.
 	var deducePkgsGroup sync.WaitGroup
 	deductionErrs := make(DeductionErrs)
@@ -420,6 +431,10 @@ func ValidateParams(params SolveParameters, sm SourceManager) error {
 	}
 
 	for _, ip := range rd.externalImportList(paths.IsStandardImportPath) {
+		if altSrc[ip] {
+			// Skip project root deduction for project with alternate source.
+			continue
+		}
 		deducePkgsGroup.Add(1)
 		go deducePkg(ip, sm)
 	}

manifest.go

@@ -304,15 +304,37 @@ func ValidateProjectRoots(c *Ctx, m *Manifest, sm gps.SourceManager) error {
 		}
 	}
 
-	for pr := range m.Constraints {
+	// A map to register projects with alternate source.
+	projectsWithAltSrc := make(map[gps.ProjectRoot]bool)
+
+	for pr, pp := range m.Constraints {
+		// If an alternate source is specified, it could be to bypass some network
+		// reachability issue. Trying to deduce ProjectRoot would fail if the
+		// the project isn't reachable. Do not validate such ProjectRoots.
+		if pp.Source != "" {
+			projectsWithAltSrc[pr] = true
+			continue
+		}
+
 		wg.Add(1)
 		go validate(pr)
 	}
-	for pr := range m.Ovr {
+	for pr, pp := range m.Ovr {
+		// Skip validation for alternate source.
+		if pp.Source != "" {
+			projectsWithAltSrc[pr] = true
+			continue
+		}
+
 		wg.Add(1)
 		go validate(pr)
 	}
 	for pr := range m.PruneOptions.PerProjectOptions {
+		// Skip validation for alternate source.
+		if projectsWithAltSrc[pr] {
+			continue
+		}
+
 		wg.Add(1)
 		go validate(pr)
 	}

manifest_test.go

@@ -618,6 +618,20 @@ func TestValidateProjectRoots(t *testing.T) {
 			wantError: errInvalidProjectRoot,
 			wantWarn:  []string{},
 		},
+		{
+			name: "skip project root deduction for alternate source",
+			manifest: Manifest{
+				Constraints: map[gps.ProjectRoot]gps.ProjectProperties{
+					// bad ProjectRoot
+					gps.ProjectRoot("golang.org/x"): {
+						Constraint: gps.NewBranch("master"),
+						Source:     "github.com/golang/text",
+					},
+				},
+			},
+			wantError: nil,
+			wantWarn:  []string{},
+		},
 	}
 
 	h := test.NewHelper(t)