From 8bedb085c642f0ef8d4e3d732c198aa42775f196 Mon Sep 17 00:00:00 2001
From: mstrong <mstrong1341@gmail.com>
Date: Sun, 1 Oct 2017 13:18:08 -0500
Subject: [PATCH] Prefetch and log output during InitializeRootManifestAndLock

---
 cmd/dep/init.go          |  2 +-
 cmd/dep/root_analyzer.go | 71 +++++++++++++++++++++++++++++++++++++++-
 2 files changed, 71 insertions(+), 2 deletions(-)

diff --git a/cmd/dep/init.go b/cmd/dep/init.go
index 4cebf4ae34..2cc6cbc5be 100644
--- a/cmd/dep/init.go
+++ b/cmd/dep/init.go
@@ -146,7 +146,7 @@ func (cmd *initCommand) Run(ctx *dep.Ctx, args []string) error {
 
 	// Initialize with imported data, then fill in the gaps using the GOPATH
 	rootAnalyzer := newRootAnalyzer(cmd.skipTools, ctx, directDeps, sm)
-	p.Manifest, p.Lock, err = rootAnalyzer.InitializeRootManifestAndLock(root, p.ImportRoot)
+	p.Manifest, p.Lock, err = rootAnalyzer.InitializeRootManifestAndLock(root, p.ImportRoot, pkgT)
 	if err != nil {
 		return err
 	}
diff --git a/cmd/dep/root_analyzer.go b/cmd/dep/root_analyzer.go
index c300eadad8..04f7ca8b20 100644
--- a/cmd/dep/root_analyzer.go
+++ b/cmd/dep/root_analyzer.go
@@ -5,12 +5,15 @@
 package main
 
 import (
+	"fmt"
 	"io/ioutil"
 	"log"
+	"strings"
 
 	"github.com/golang/dep"
 	fb "github.com/golang/dep/internal/feedback"
 	"github.com/golang/dep/internal/gps"
+	"github.com/golang/dep/internal/gps/pkgtree"
 	"github.com/golang/dep/internal/importers"
 )
 
@@ -35,7 +38,7 @@ func newRootAnalyzer(skipTools bool, ctx *dep.Ctx, directDeps map[string]bool, s
 	}
 }
 
-func (a *rootAnalyzer) InitializeRootManifestAndLock(dir string, pr gps.ProjectRoot) (rootM *dep.Manifest, rootL *dep.Lock, err error) {
+func (a *rootAnalyzer) InitializeRootManifestAndLock(dir string, pr gps.ProjectRoot, pkgT pkgtree.PackageTree) (rootM *dep.Manifest, rootL *dep.Lock, err error) {
 	if !a.skipTools {
 		rootM, rootL, err = a.importManifestAndLock(dir, pr, false)
 		if err != nil {
@@ -45,6 +48,7 @@ func (a *rootAnalyzer) InitializeRootManifestAndLock(dir string, pr gps.ProjectR
 
 	if rootM == nil {
 		rootM = dep.NewManifest()
+		a.cacheDeps(pr, pkgT)
 	}
 	if rootL == nil {
 		rootL = &dep.Lock{}
@@ -53,6 +57,71 @@ func (a *rootAnalyzer) InitializeRootManifestAndLock(dir string, pr gps.ProjectR
 	return
 }
 
+func (a *rootAnalyzer) cacheDeps(pr gps.ProjectRoot, pkgT pkgtree.PackageTree) {
+	packages := make(map[string]bool)
+	dependencies := make(map[gps.ProjectRoot][]string)
+	logger := a.ctx.Err
+
+	syncDep := func(pr gps.ProjectRoot, sm gps.SourceManager) {
+		message := fmt.Sprintf("Cached %s", pr)
+		if err := sm.SyncSourceFor(gps.ProjectIdentifier{ProjectRoot: pr}); err != nil {
+			message = fmt.Sprintf("Unable to cache %s - %s", pr, err)
+		}
+		logger.Printf(message)
+	}
+
+	for _, v := range pkgT.Packages {
+		// TODO: Some errors maybe should not be skipped ;-)
+		if v.Err != nil {
+			logger.Printf("%v", v.Err)
+			continue
+		}
+
+		logger.Printf("Package %q, analyzing...", v.P.ImportPath)
+
+		for _, ip := range v.P.Imports {
+			if isStdLib(ip) {
+				continue
+			}
+			if hasImportPathPrefix(ip, string(pr)) {
+				continue
+			}
+
+			pr, err := a.sm.DeduceProjectRoot(ip)
+			if err != nil {
+				// return nil, nil, nil
+			}
+
+			packages[ip] = true
+			if _, ok := dependencies[pr]; ok {
+				if !contains(dependencies[pr], ip) {
+					dependencies[pr] = append(dependencies[pr], ip)
+				}
+				continue
+			}
+
+			go syncDep(pr, a.sm)
+			dependencies[pr] = []string{ip}
+		}
+	}
+}
+
+func hasImportPathPrefix(s, prefix string) bool {
+	if s == prefix {
+		return true
+	}
+	return strings.HasPrefix(s, prefix+"/")
+}
+
+func isStdLib(path string) bool {
+	i := strings.Index(path, "/")
+	if i < 0 {
+		i = len(path)
+	}
+	elem := path[:i]
+	return !strings.Contains(elem, ".")
+}
+
 func (a *rootAnalyzer) importManifestAndLock(dir string, pr gps.ProjectRoot, suppressLogs bool) (*dep.Manifest, *dep.Lock, error) {
 	logger := a.ctx.Err
 	if suppressLogs {