cmd/cue: implement cue mod get

This adds the capability to update a module version or add a new dependency. The functionality is more limited than that provided by `go get`: - arguments are modules, not packages - downgrade functionality is much more limited (cannot downgrade when that's in conflict with other requirements) - no support for arbitrary dependency constraints such as `<v1.2.3` - only "latest" and version prefixes are supported. Fixes #2867. Signed-off-by: Roger Peppe <[email protected]> Change-Id: I7fc4d8a2f033a48ee0761ae4dbbf5979711f6189 Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1177696 Reviewed-by: Daniel Martí <[email protected]> TryBot-Result: CUEcueckoo <[email protected]>
cue-lang · Mar 4, 2024 · 93643a3 · 93643a3
1 parent 2dc8879
commit 93643a3
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Showing 5 changed files with 405 additions and 23 deletions.
diff --git a/cmd/cue/cmd/mod.go b/cmd/cue/cmd/mod.go
@@ -47,10 +47,11 @@ func newModCmd(c *Command) *cobra.Command {
 		}),
 	}
 
+	cmd.AddCommand(newModGetCmd(c))
 	cmd.AddCommand(newModInitCmd(c))
-	cmd.AddCommand(newModUploadCmd(c))
-	cmd.AddCommand(newModTidyCmd(c))
 	cmd.AddCommand(newModRegistryCmd(c))
+	cmd.AddCommand(newModTidyCmd(c))
+	cmd.AddCommand(newModUploadCmd(c))
 	return cmd
 }
 

diff --git a/cmd/cue/cmd/modget.go b/cmd/cue/cmd/modget.go
@@ -0,0 +1,125 @@
+// Copyright 2024 The CUE Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package cmd
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/spf13/cobra"
+
+	"cuelang.org/go/internal/mod/modload"
+)
+
+func newModGetCmd(c *Command) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "get",
+		Short: "add and upgrade module dependencies",
+		Long: `WARNING: THIS COMMAND IS EXPERIMENTAL.
+
+Get updates module dependencies, fetching new dependencies if
+needed and changing versions to specified versions. It can downgrade
+a version only when a higher version is not required by other
+dependencies.
+
+Each argument specifies a module path and optionally a version
+suffix. If there is no version suffix, the latest non-prerelease version
+of the module will be requested; alternatively a suffix of "@latest"
+also specifies the latest version.
+
+A version suffix can contain a major version only (@v1), a major and minor
+version (@v1.2) or full version (@v1.2.3). If minor or patch version is omitted, the
+latest non-prerelease version will be chosen that has the same major
+and minor versions.
+
+If the desired version cannot be chosen (for example because a
+dependency already uses a later version than the desired version),
+this command will fail.
+
+See "cue help environment" for details on how $CUE_REGISTRY is used to
+determine the modules registry.
+
+Note: you must enable the modules experiment with:
+	export CUE_EXPERIMENT=modules
+for this command to work.
+`,
+		RunE: mkRunE(c, runModGet),
+		Args: cobra.MinimumNArgs(1),
+	}
+
+	return cmd
+}
+
+func runModGet(cmd *Command, args []string) error {
+	reg, err := getCachedRegistry()
+	if err != nil {
+		return err
+	}
+	if reg == nil {
+		return fmt.Errorf("modules experiment not enabled (enable with CUE_EXPERIMENT=modules)")
+	}
+	ctx := context.Background()
+	modRoot, err := findModuleRoot()
+	if err != nil {
+		return err
+	}
+	mf, err := modload.UpdateVersions(ctx, os.DirFS(modRoot), ".", reg, args)
+	if err != nil {
+		return err
+	}
+	// TODO check whether it's changed or not.
+	data, err := mf.Format()
+	if err != nil {
+		return fmt.Errorf("internal error: invalid module.cue file generated: %v", err)
+	}
+	modPath := filepath.Join(modRoot, "cue.mod", "module.cue")
+	oldData, err := os.ReadFile(modPath)
+	if err != nil {
+		// Shouldn't happen because modload.Load returns an error
+		// if it can't load the module file.
+		return err
+	}
+	if bytes.Equal(data, oldData) {
+		return nil
+	}
+	if err := os.WriteFile(modPath, data, 0o666); err != nil {
+		return err
+	}
+	return nil
+}
+
+func findModuleRoot() (string, error) {
+	// TODO this logic is duplicated in multiple places. We should
+	// consider deduplicating it.
+	dir, err := os.Getwd()
+	if err != nil {
+		return "", err
+	}
+	for {
+		if _, err := os.Stat(filepath.Join(dir, "cue.mod")); err == nil {
+			return dir, nil
+		} else if !os.IsNotExist(err) {
+			return "", err
+		}
+		dir1 := filepath.Dir(dir)
+		if dir1 == dir {
+			return "", fmt.Errorf("module root not found")
+		}
+		dir = dir1
+	}
+}
diff --git a/cmd/cue/cmd/modtidy.go b/cmd/cue/cmd/modtidy.go
@@ -92,24 +92,3 @@ func runModTidy(cmd *Command, args []string) error {
 	}
 	return nil
 }
-
-func findModuleRoot() (string, error) {
-	// TODO this logic is duplicated in multiple places. We should
-	// consider deduplicating it.
-	dir, err := os.Getwd()
-	if err != nil {
-		return "", err
-	}
-	for {
-		if _, err := os.Stat(filepath.Join(dir, "cue.mod")); err == nil {
-			return dir, nil
-		} else if !os.IsNotExist(err) {
-			return "", err
-		}
-		dir1 := filepath.Dir(dir)
-		if dir1 == dir {
-			return "", fmt.Errorf("module root not found")
-		}
-		dir = dir1
-	}
-}
diff --git a/cmd/cue/cmd/testdata/script/modget_initial.txtar b/cmd/cue/cmd/testdata/script/modget_initial.txtar
@@ -0,0 +1,231 @@
+# Check that cue mod get will upgrade an existing
+# dependency.
+cp cue.mod/module.cue module-original
+
+# cue mod get should update to v0.10.2 but not to the
+# latest prerelease v0.11.0-alpha
+exec cue mod get baz.org
+cmp cue.mod/module.cue want-module-1
+exec cue export .
+cmp stdout want-stdout-1
+
+# Check that the same thing happens when we use an
+# explicit @latest suffix.
+cp module-original cue.mod/module.cue
+exec cue mod get baz.org@latest
+cmp cue.mod/module.cue want-module-1
+exec cue export .
+cmp stdout want-stdout-1
+
+# We can update to the latest prerelease by providing an
+# explicit version.
+exec cue mod get [email protected]
+cmp cue.mod/module.cue want-module-2
+exec cue export .
+cmp stdout want-stdout-2
+
+# Check that we can also do the above by specifying
+# an explicit v0.11 prefix
+cp want-module-1 cue.mod/module.cue
+exec cue mod get [email protected]
+cmp cue.mod/module.cue want-module-2
+exec cue export .
+cmp stdout want-stdout-2
+
+# If we try it again without an argument, it'll downgrade.
+exec cue mod get baz.org
+cmp cue.mod/module.cue want-module-1
+exec cue export .
+cmp stdout want-stdout-1
+
+# If we try to downgrade when some other dependency
+# is reliant on a later version, we'll get an error.
+! exec cue mod get [email protected]
+stderr 'other requirements prevent changing module baz.org@v0 to version v0.5.0 \(actual selected version: v0.10.1\)'
+
+-- want-module-1 --
+module: "main.org@v0"
+deps: {
+	"bar.com@v0": {
+		v: "v0.5.0"
+	}
+	"baz.org@v0": {
+		v: "v0.10.2"
+	}
+	"example.com@v0": {
+		v: "v0.0.1"
+	}
+	"foo.com/bar/hello@v0": {
+		v:       "v0.2.3"
+		default: true
+	}
+}
+-- want-stdout-1 --
+{
+    "main": "main",
+    "foo.com/bar/hello@v0": "v0.2.3",
+    "bar.com@v0": "v0.5.0",
+    "baz.org@v0": "v0.10.2",
+    "example.com@v0": "v0.0.1"
+}
+-- want-module-2 --
+module: "main.org@v0"
+deps: {
+	"bar.com@v0": {
+		v: "v0.5.0"
+	}
+	"baz.org@v0": {
+		v: "v0.11.0-alpha"
+	}
+	"example.com@v0": {
+		v: "v0.0.1"
+	}
+	"foo.com/bar/hello@v0": {
+		v:       "v0.2.3"
+		default: true
+	}
+}
+-- want-stdout-2 --
+{
+    "main": "main",
+    "foo.com/bar/hello@v0": "v0.2.3",
+    "bar.com@v0": "v0.5.0",
+    "baz.org@v0": "v0.11.0-alpha",
+    "example.com@v0": "v0.0.1"
+}
+-- cue.mod/module.cue --
+module: "main.org@v0"
+deps: {
+	"bar.com@v0": {
+		v: "v0.5.0"
+	}
+	"baz.org@v0": {
+		v: "v0.10.1"
+	}
+	"example.com@v0": {
+		v: "v0.0.1"
+	}
+	"foo.com/bar/hello@v0": {
+		v:       "v0.2.3"
+		default: true
+	}
+}
+
+-- main.cue --
+package main
+import "example.com@v0:main"
+
+main
+
+-- _registry/example.com_v0.0.1/cue.mod/module.cue --
+module: "example.com@v0"
+deps: {
+	"foo.com/bar/hello@v0": v: "v0.2.3"
+	"bar.com@v0": v: "v0.5.0"
+}
+
+-- _registry/example.com_v0.0.1/top.cue --
+package main
+
+import a "foo.com/bar/hello"
+a
+main: "main"
+"example.com@v0": "v0.0.1"
+
+-- _registry/example.com_v0.1.2/cue.mod/module.cue --
+module: "example.com@v0"
+
+-- _registry/example.com_v0.1.2/top.cue --
+package main
+"example.com@v0": "v0.1.2"
+
+// TODO: import without a major version should
+// the major version from the module.cue file.
+main: "main"
+"example.com@v0": "v0.0.1"
+
+-- _registry/foo.com_bar_hello_v0.2.3/cue.mod/module.cue --
+module: "foo.com/bar/hello@v0"
+deps: {
+	"bar.com@v0": v: "v0.0.2"
+	"baz.org@v0": v: "v0.10.1"
+}
+
+-- _registry/foo.com_bar_hello_v0.2.3/x.cue --
+package hello
+import (
+	a "bar.com/bar@v0"
+	b "baz.org@v0:baz"
+)
+"foo.com/bar/hello@v0": "v0.2.3"
+a
+b
+
+
+-- _registry/bar.com_v0.0.2/cue.mod/module.cue --
+module: "bar.com@v0"
+deps: "baz.org@v0": v: "v0.0.2"
+
+-- _registry/bar.com_v0.0.2/bar/x.cue --
+package bar
+import a "baz.org@v0:baz"
+"bar.com@v0": "v0.0.2"
+a
+
+
+-- _registry/bar.com_v0.5.0/cue.mod/module.cue --
+module: "bar.com@v0"
+deps: "baz.org@v0": v: "v0.5.0"
+
+-- _registry/bar.com_v0.5.0/bar/x.cue --
+package bar
+import a "baz.org@v0:baz"
+"bar.com@v0": "v0.5.0"
+a
+
+
+-- _registry/baz.org_v0.0.2/cue.mod/module.cue --
+module: "baz.org@v0"
+
+-- _registry/baz.org_v0.0.2/baz.cue --
+package baz
+"baz.org@v0": "v0.0.2"
+
+
+-- _registry/baz.org_v0.1.2/cue.mod/module.cue --
+module: "baz.org@v0"
+
+-- _registry/baz.org_v0.1.2/baz.cue --
+package baz
+"baz.org@v0": "v0.1.2"
+
+
+-- _registry/baz.org_v0.5.0/cue.mod/module.cue --
+module: "baz.org@v0"
+
+-- _registry/baz.org_v0.5.0/baz.cue --
+package baz
+"baz.org@v0": "v0.5.0"
+
+
+-- _registry/baz.org_v0.10.1/cue.mod/module.cue --
+module: "baz.org@v0"
+
+-- _registry/baz.org_v0.10.1/baz.cue --
+package baz
+"baz.org@v0": "v0.10.1"
+
+
+-- _registry/baz.org_v0.10.2/cue.mod/module.cue --
+module: "baz.org@v0"
+
+-- _registry/baz.org_v0.10.2/baz.cue --
+package baz
+"baz.org@v0": "v0.10.2"
+
+-- _registry/baz.org_v0.11.0-alpha/cue.mod/module.cue --
+module: "baz.org@v0"
+
+-- _registry/baz.org_v0.11.0-alpha/baz.cue --
+package baz
+"baz.org@v0": "v0.11.0-alpha"