command: Add vars to validate command

internal/command/arguments/validate.go

@@ -27,6 +27,8 @@ type Validate struct {
 
 	// Query indicates that Terraform should also validate .tfquery files.
 	Query bool
+
+	Vars *Vars
 }
 
 // ParseValidate processes CLI arguments, returning a Validate value and errors.
@@ -36,10 +38,11 @@ func ParseValidate(args []string) (*Validate, tfdiags.Diagnostics) {
 	var diags tfdiags.Diagnostics
 	validate := &Validate{
 		Path: ".",
+		Vars: &Vars{},
 	}
 
 	var jsonOutput bool
-	cmdFlags := defaultFlagSet("validate")
+	cmdFlags := extendedFlagSet("validate", nil, nil, validate.Vars)
 	cmdFlags.BoolVar(&jsonOutput, "json", false, "json")
 	cmdFlags.StringVar(&validate.TestDirectory, "test-directory", "tests", "test-directory")
 	cmdFlags.BoolVar(&validate.NoTests, "no-tests", false, "no-tests")

internal/command/arguments/validate_test.go

@@ -6,6 +6,8 @@ package arguments
 import (
 	"testing"
 
+	"github.com/google/go-cmp/cmp"
+	"github.com/google/go-cmp/cmp/cmpopts"
 	"github.com/hashicorp/terraform/internal/tfdiags"
 )
 
@@ -19,6 +21,7 @@ func TestParseValidate_valid(t *testing.T) {
 			&Validate{
 				Path:          ".",
 				TestDirectory: "tests",
+				Vars:          &Vars{},
 				ViewType:      ViewHuman,
 			},
 		},
@@ -27,6 +30,7 @@ func TestParseValidate_valid(t *testing.T) {
 			&Validate{
 				Path:          ".",
 				TestDirectory: "tests",
+				Vars:          &Vars{},
 				ViewType:      ViewJSON,
 			},
 		},
@@ -35,6 +39,7 @@ func TestParseValidate_valid(t *testing.T) {
 			&Validate{
 				Path:          "foo",
 				TestDirectory: "tests",
+				Vars:          &Vars{},
 				ViewType:      ViewJSON,
 			},
 		},
@@ -43,6 +48,7 @@ func TestParseValidate_valid(t *testing.T) {
 			&Validate{
 				Path:          ".",
 				TestDirectory: "other",
+				Vars:          &Vars{},
 				ViewType:      ViewHuman,
 			},
 		},
@@ -51,25 +57,72 @@ func TestParseValidate_valid(t *testing.T) {
 			&Validate{
 				Path:          ".",
 				TestDirectory: "tests",
+				Vars:          &Vars{},
 				ViewType:      ViewHuman,
 				NoTests:       true,
 			},
 		},
 	}
 
+	cmpOpts := cmpopts.IgnoreUnexported(Vars{})
+
 	for name, tc := range testCases {
 		t.Run(name, func(t *testing.T) {
 			got, diags := ParseValidate(tc.args)
 			if len(diags) > 0 {
 				t.Fatalf("unexpected diags: %v", diags)
 			}
-			if *got != *tc.want {
+			if diff := cmp.Diff(tc.want, got, cmpOpts); diff != "" {
 				t.Fatalf("unexpected result\n got: %#v\nwant: %#v", got, tc.want)
 			}
 		})
 	}
 }
 
+func TestParseValidate_vars(t *testing.T) {
+	testCases := map[string]struct {
+		args []string
+		want []FlagNameValue
+	}{
+		"var": {
+			args: []string{"-var", "foo=bar"},
+			want: []FlagNameValue{
+				{Name: "-var", Value: "foo=bar"},
+			},
+		},
+		"var-file": {
+			args: []string{"-var-file", "cool.tfvars"},
+			want: []FlagNameValue{
+				{Name: "-var-file", Value: "cool.tfvars"},
+			},
+		},
+		"both": {
+			args: []string{
+				"-var", "foo=bar",
+				"-var-file", "cool.tfvars",
+				"-var", "boop=beep",
+			},
+			want: []FlagNameValue{
+				{Name: "-var", Value: "foo=bar"},
+				{Name: "-var-file", Value: "cool.tfvars"},
+				{Name: "-var", Value: "boop=beep"},
+			},
+		},
+	}
+
+	for name, tc := range testCases {
+		t.Run(name, func(t *testing.T) {
+			got, diags := ParseValidate(tc.args)
+			if len(diags) > 0 {
+				t.Fatalf("unexpected diags: %v", diags)
+			}
+			if vars := got.Vars.All(); !cmp.Equal(vars, tc.want) {
+				t.Fatalf("unexpected vars: %#v", vars)
+			}
+		})
+	}
+}
+
 func TestParseValidate_invalid(t *testing.T) {
 	testCases := map[string]struct {
 		args      []string
@@ -81,6 +134,7 @@ func TestParseValidate_invalid(t *testing.T) {
 			&Validate{
 				Path:          ".",
 				TestDirectory: "tests",
+				Vars:          &Vars{},
 				ViewType:      ViewHuman,
 			},
 			tfdiags.Diagnostics{
@@ -96,6 +150,7 @@ func TestParseValidate_invalid(t *testing.T) {
 			&Validate{
 				Path:          "bar",
 				TestDirectory: "tests",
+				Vars:          &Vars{},
 				ViewType:      ViewJSON,
 			},
 			tfdiags.Diagnostics{
@@ -108,10 +163,12 @@ func TestParseValidate_invalid(t *testing.T) {
 		},
 	}
 
+	cmpOpts := cmpopts.IgnoreUnexported(Vars{})
+
 	for name, tc := range testCases {
 		t.Run(name, func(t *testing.T) {
 			got, gotDiags := ParseValidate(tc.args)
-			if *got != *tc.want {
+			if diff := cmp.Diff(tc.want, got, cmpOpts); diff != "" {
 				t.Fatalf("unexpected result\n got: %#v\nwant: %#v", got, tc.want)
 			}
 			tfdiags.AssertDiagnosticsMatch(t, gotDiags, tc.wantDiags)

internal/command/validate.go

@@ -47,6 +47,26 @@ func (c *ValidateCommand) Run(rawArgs []string) int {
 	c.ParsedArgs = args
 	view := views.NewValidate(args.ViewType, c.View)
 
+	// If the query flag is set, include query files in the validation.
+	c.includeQueryFiles = c.ParsedArgs.Query
+
+	loader, err := c.initConfigLoader()
+	if err != nil {
+		diags = diags.Append(err)
+		view.Diagnostics(diags)
+		return 1
+	}
+
+	var varDiags tfdiags.Diagnostics
+	c.VariableValues, varDiags = args.Vars.CollectValues(func(filename string, src []byte) {
+		loader.Parser().ForceFileSource(filename, src)
+	})
+	diags = diags.Append(varDiags)
+	if diags.HasErrors() {
+		view.Diagnostics(diags)
+		return 1
+	}
+
 	// After this point, we must only produce JSON output if JSON mode is
 	// enabled, so all errors should be accumulated into diags and we'll
 	// print out a suitable result at the end, depending on the format
@@ -81,9 +101,6 @@ func (c *ValidateCommand) validate(dir string) tfdiags.Diagnostics {
 	var diags tfdiags.Diagnostics
 	var cfg *configs.Config
 
-	// If the query flag is set, include query files in the validation.
-	c.includeQueryFiles = c.ParsedArgs.Query
-
 	if c.ParsedArgs.NoTests {
 		cfg, diags = c.loadConfig(dir)
 	} else {
@@ -360,9 +377,19 @@ Options:
 
   -no-tests             If specified, Terraform will not validate test files.
 
-  -test-directory=path	Set the Terraform test directory, defaults to "tests".
-  
+  -test-directory=path  Set the Terraform test directory, defaults to "tests".
+
   -query                If specified, the command will also validate .tfquery.hcl files.
+
+  -var 'foo=bar'        Set a value for one of the input variables in the root
+                        module of the configuration. Use this option more than
+                        once to set more than one variable.
+
+  -var-file=filename    Load variable values from the given file, in addition
+                        to the default files terraform.tfvars and *.auto.tfvars.
+                        Use this option more than once to include more than one
+                        variables file.
+
 `
 	return strings.TrimSpace(helpText)
 }