Merge pull request #2415 from melsonic/issue-2410

cli: add validate command

ci/release/changelogs/next.md

@@ -24,6 +24,9 @@
   - Support relative imports. Improve elk error handling: [#2382](https://github.com/terrastruct/d2/pull/2382)
   - Support fonts (`fontRegular`, `fontItalic`, `fontBold`, `fontSemiBold`): [#2384](https://github.com/terrastruct/d2/pull/2384)
 
+- d2cli:
+    - Support `validate` command. [#2415](https://github.com/terrastruct/d2/pull/2415)
+
 #### Bugfixes ⛑️
 
 - Compiler:

ci/release/template/man/d2.1

@@ -17,6 +17,8 @@
 .Ar fmt Ar file.d2 ...
 .Nm d2
 .Ar play Ar file.d2
+.Nm d2
+.Ar validate Ar file.d2
 .Sh DESCRIPTION
 .Nm
 compiles and renders
@@ -162,6 +164,8 @@ Lists available themes
 Format all passed files
 .It Ar play Ar file.d2
 Opens the file in playground, an online web viewer (https://play.d2lang.com)
+.It Ar validate Ar file.d2
+Validates file.d2
 .El
 .Sh ENVIRONMENT VARIABLES
 Many flags can also be set with environment variables.

d2cli/help.go

@@ -23,6 +23,7 @@ Usage:
   %[1]s layout [name]
   %[1]s fmt file.d2 ...
   %[1]s play [--theme=0] [--sketch] file.d2
+  %[1]s validate file.d2
 
 %[1]s compiles and renders file.d2 to file.svg | file.png
 It defaults to file.svg if an output path is not provided.
@@ -40,6 +41,7 @@ Subcommands:
   %[1]s themes - Lists available themes
   %[1]s fmt file.d2 ... - Format passed files
 	%[1]s play file.d2 - Opens the file in playground, an online web viewer (https://play.d2lang.com)
+  %[1]s validate file.d2  - Validates file.d2
 
 See more docs and the source code at https://oss.terrastruct.com/d2.
 Hosted icons at https://icons.terrastruct.com.

d2cli/main.go

@@ -173,6 +173,8 @@ func Run(ctx context.Context, ms *xmain.State) (err error) {
 			return fmtCmd(ctx, ms, *checkFlag)
 		case "play":
 			return playCmd(ctx, ms)
+		case "validate":
+			return validateCmd(ctx, ms)
 		case "version":
 			if len(ms.Opts.Flags.Args()) > 1 {
 				return xmain.UsageErrorf("version subcommand accepts no arguments")

d2cli/validate.go

@@ -0,0 +1,41 @@
+package d2cli
+
+import (
+	"context"
+	"fmt"
+
+	"oss.terrastruct.com/d2/d2lib"
+	"oss.terrastruct.com/util-go/xdefer"
+	"oss.terrastruct.com/util-go/xmain"
+)
+
+func validateCmd(ctx context.Context, ms *xmain.State) (err error) {
+	defer xdefer.Errorf(&err, "")
+
+	ms.Opts = xmain.NewOpts(ms.Env, ms.Opts.Flags.Args()[1:])
+	if len(ms.Opts.Args) == 0 {
+		return xmain.UsageErrorf("input argument required")
+	}
+
+	inputPath := ms.Opts.Args[0]
+	if inputPath != "-" {
+		inputPath = ms.AbsPath(inputPath)
+	}
+
+	input, err := ms.ReadPath(inputPath)
+	if err != nil {
+		return err
+	}
+
+	_, err = d2lib.Parse(ctx, string(input), nil)
+	if err != nil {
+		return err
+	}
+
+	if inputPath == "-" {
+		inputPath = "Input"
+	}
+
+	fmt.Printf("Success! [%s] is valid D2.\n", inputPath)
+	return nil
+}

e2etests-cli/main_test.go

@@ -1346,6 +1346,22 @@ c
 				assert.Success(t, err)
 			},
 		},
+		{
+			name: "validate-against-correct-d2",
+			run: func(t *testing.T, ctx context.Context, dir string, env *xos.Env) {
+				writeFile(t, dir, "correct.d2", `x -> y`)
+				err := runTestMainPersist(t, ctx, dir, env, "validate", "correct.d2")
+				assert.Success(t, err)
+			},
+		},
+		{
+			name: "validate-against-incorrect-d2",
+			run: func(t *testing.T, ctx context.Context, dir string, env *xos.Env) {
+				writeFile(t, dir, "incorrect.d2", `x > y`)
+				err := runTestMainPersist(t, ctx, dir, env, "validate", "incorrect.d2")
+				assert.Error(t, err)
+			},
+		},
 	}
 
 	ctx := context.Background()