cmd/go/internal/modload: avoid using the global build list in QueryPattern

The Query function allows the caller to specify the current version of
the requested module, but the QueryPattern function is missing that
parameter: instead, it always assumes that the current version is the
one selected from the global build list.

This change removes that assumption, instead adding a callback
function to determine the current version. (The callback is currently
invoked once per candidate module, regardless of whether that module
exists, but in a future change we can refactor it to invoke the
callback only when needed.)

For #36460
For #40775

Change-Id: I001a4a8ab24f5b4fcc66a670d9bd305b47e948ba
Reviewed-on: https://go-review.googlesource.com/c/go/+/261640
Trust: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>
Reviewed-by: Michael Matloob <matloob@golang.org>

diff --git a/src/cmd/go/internal/modget/get.go b/src/cmd/go/internal/modget/get.go
index 9e2fb8e408817dc254790b4f04c9df6c09f14e66..171c070ab342df2357e2fca2fb446bc51f2f0c79 100644 (file)
--- a/src/cmd/go/internal/modget/get.go
+++ b/src/cmd/go/internal/modget/get.go
@@ -912,7 +912,7 @@ func getQuery(ctx context.Context, path, vers string, prevM module.Version, forc
        // If it turns out to only exist as a module, we can detect the resulting
        // PackageNotInModuleError and avoid a second round-trip through (potentially)
        // all of the configured proxies.
-       results, err := modload.QueryPattern(ctx, path, vers, allowed)
+       results, err := modload.QueryPattern(ctx, path, vers, modload.Selected, allowed)
        if err != nil {
                // If the path doesn't contain a wildcard, check whether it was actually a
                // module path instead. If so, return that.

diff --git a/src/cmd/go/internal/modload/buildlist.go b/src/cmd/go/internal/modload/buildlist.go
index 059b0204206d5db47d3b37dc47b0484a0f3dc6c2..95a68637c665cad6d02257d0bac66667e92a05b2 100644 (file)
--- a/src/cmd/go/internal/modload/buildlist.go
+++ b/src/cmd/go/internal/modload/buildlist.go
@@ -52,6 +52,21 @@ func LoadedModules() []module.Version {
        return buildList
 }
 
+// Selected returns the selected version of the module with the given path, or
+// the empty string if the given module has no selected version
+// (either because it is not required or because it is the Target module).
+func Selected(path string) (version string) {
+       if path == Target.Path {
+               return ""
+       }
+       for _, m := range buildList {
+               if m.Path == path {
+                       return m.Version
+               }
+       }
+       return ""
+}
+
 // SetBuildList sets the module build list.
 // The caller is responsible for ensuring that the list is valid.
 // SetBuildList does not retain a reference to the original list.

diff --git a/src/cmd/go/internal/modload/import.go b/src/cmd/go/internal/modload/import.go
index 1c572d5d6debf60bc2cf687afabe13b1ac449136..6d0d8de94459403ac1e18910c4b65a8611f2dbb0 100644 (file)
--- a/src/cmd/go/internal/modload/import.go
+++ b/src/cmd/go/internal/modload/import.go
@@ -345,7 +345,7 @@ func queryImport(ctx context.Context, path string) (module.Version, error) {
        // and return m, dir, ImpportMissingError.
        fmt.Fprintf(os.Stderr, "go: finding module for package %s\n", path)
 
-       candidates, err := QueryPattern(ctx, path, "latest", CheckAllowed)
+       candidates, err := QueryPattern(ctx, path, "latest", Selected, CheckAllowed)
        if err != nil {
                if errors.Is(err, os.ErrNotExist) {
                        // Return "cannot find module providing package […]" instead of whatever

diff --git a/src/cmd/go/internal/modload/modfile.go b/src/cmd/go/internal/modload/modfile.go
index d15da892e6db48ba7c4b30c53cc25e5d6be49fc4..006db4f169ebe5308b9dd89c6ed19dfd5b2bb7bb 100644 (file)
--- a/src/cmd/go/internal/modload/modfile.go
+++ b/src/cmd/go/internal/modload/modfile.go
@@ -116,7 +116,7 @@ func checkRetractions(ctx context.Context, m module.Version) error {
                // Ignore exclusions from the main module's go.mod.
                // We may need to account for the current version: for example,
                // v2.0.0+incompatible is not "latest" if v1.0.0 is current.
-               rev, err := Query(ctx, path, "latest", findCurrentVersion(path), nil)
+               rev, err := Query(ctx, path, "latest", Selected(path), nil)
                if err != nil {
                        return &entry{nil, err}
                }

diff --git a/src/cmd/go/internal/modload/query.go b/src/cmd/go/internal/modload/query.go
index 6a3fd103fcdea03918dd39d75ca056612700fae3..d16a247f727e518f09140eaa70e2b15b3e4bc572 100644 (file)
--- a/src/cmd/go/internal/modload/query.go
+++ b/src/cmd/go/internal/modload/query.go
@@ -516,7 +516,7 @@ type QueryResult struct {
 // If any matching package is in the main module, QueryPattern considers only
 // the main module and only the version "latest", without checking for other
 // possible modules.
-func QueryPattern(ctx context.Context, pattern, query string, allowed AllowedFunc) ([]QueryResult, error) {
+func QueryPattern(ctx context.Context, pattern, query string, current func(string) string, allowed AllowedFunc) ([]QueryResult, error) {
        ctx, span := trace.StartSpan(ctx, "modload.QueryPattern "+pattern+" "+query)
        defer span.Done()
 
@@ -591,9 +591,9 @@ func QueryPattern(ctx context.Context, pattern, query string, allowed AllowedFun
                        ctx, span := trace.StartSpan(ctx, "modload.QueryPattern.queryModule ["+proxy+"] "+path)
                        defer span.Done()
 
-                       current := findCurrentVersion(path)
+                       pathCurrent := current(path)
                        r.Mod.Path = path
-                       r.Rev, err = queryProxy(ctx, proxy, path, query, current, allowed)
+                       r.Rev, err = queryProxy(ctx, proxy, path, query, pathCurrent, allowed)
                        if err != nil {
                                return r, err
                        }
@@ -649,15 +649,6 @@ func modulePrefixesExcludingTarget(path string) []string {
        return prefixes
 }
 
-func findCurrentVersion(path string) string {
-       for _, m := range buildList {
-               if m.Path == path {
-                       return m.Version
-               }
-       }
-       return ""
-}
-
 type prefixResult struct {
        QueryResult
        err error

diff --git a/src/cmd/go/internal/work/build.go b/src/cmd/go/internal/work/build.go
index 21342ac8ba00c1184194340bad05a9ae157c85f5..3531612dc6115850df336f09183f2023532403ac 100644 (file)
--- a/src/cmd/go/internal/work/build.go
+++ b/src/cmd/go/internal/work/build.go
@@ -741,7 +741,7 @@ func installOutsideModule(ctx context.Context, args []string) {
                // Don't check for retractions if a specific revision is requested.
                allowed = nil
        }
-       qrs, err := modload.QueryPattern(ctx, patterns[0], version, allowed)
+       qrs, err := modload.QueryPattern(ctx, patterns[0], version, modload.Selected, allowed)
        if err != nil {
                base.Fatalf("go install %s: %v", args[0], err)
        }