From 36958cab23981656cde11d5c554adc60175b8a7c Mon Sep 17 00:00:00 2001
From: Dieter Kling <4270462+dkling-it@users.noreply.github.com>
Date: Fri, 21 Aug 2026 21:54:34 +0200
Subject: [PATCH] clusters: make `start` a no-op when the cluster isn't
 TERMINATED

`databricks clusters start` returns an INVALID_STATE API error if the
target cluster is already RUNNING/PENDING/RESTARTING/RESIZING, even
though the command's own help text says "If the cluster is not
currently in a TERMINATED state, nothing will happen."

Wrap the generated start command's RunE (mirrors the same INVALID_STATE
handling already used in bundle/direct/dresources/cluster.go) so that
error is swallowed and treated as a successful no-op instead.

Fixes #1372

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
---
 .../cli/clusters-start-already-running.md     |  1 +
 cmd/workspace/clusters/overrides.go           | 24 ++++++++++
 cmd/workspace/clusters/overrides_test.go      | 45 +++++++++++++++++++
 3 files changed, 70 insertions(+)
 create mode 100644 .nextchanges/cli/clusters-start-already-running.md
 create mode 100644 cmd/workspace/clusters/overrides_test.go

diff --git a/.nextchanges/cli/clusters-start-already-running.md b/.nextchanges/cli/clusters-start-already-running.md
new file mode 100644
index 00000000000..4239d21d40b
--- /dev/null
+++ b/.nextchanges/cli/clusters-start-already-running.md
@@ -0,0 +1 @@
+`databricks clusters start` no longer errors when the cluster is already RUNNING (or PENDING/RESTARTING/RESIZING). It now prints a short message and exits 0, matching the command's own help text ("If the cluster is not currently in a TERMINATED state, nothing will happen").
diff --git a/cmd/workspace/clusters/overrides.go b/cmd/workspace/clusters/overrides.go
index 45c530a14a2..fb2b438e7a2 100644
--- a/cmd/workspace/clusters/overrides.go
+++ b/cmd/workspace/clusters/overrides.go
@@ -1,9 +1,12 @@
 package clusters
 
 import (
+	"errors"
+	"fmt"
 	"strings"
 
 	"github.com/databricks/cli/libs/cmdio"
+	"github.com/databricks/databricks-sdk-go/apierr"
 	"github.com/databricks/databricks-sdk-go/service/compute"
 	"github.com/spf13/cobra"
 )
@@ -93,8 +96,29 @@ func sparkVersionsOverride(sparkVersionsCmd *cobra.Command) {
 	`)
 }
 
+// The generated "start" command errors out (INVALID_STATE) if the cluster is
+// already RUNNING, PENDING, RESTARTING or RESIZING, even though the command's
+// own help text says "If the cluster is not currently in a TERMINATED state,
+// nothing will happen." This override makes the command match that
+// documented behavior instead of surfacing the API error.
+func startOverride(startCmd *cobra.Command, startReq *compute.StartCluster) {
+	originalRunE := startCmd.RunE
+	startCmd.RunE = func(cmd *cobra.Command, args []string) error {
+		err := originalRunE(cmd, args)
+
+		apiErr, ok := errors.AsType[*apierr.APIError](err)
+		if ok && apiErr.ErrorCode == "INVALID_STATE" {
+			fmt.Fprintf(cmd.OutOrStdout(), "Cluster %s is not in a TERMINATED state, nothing to do.\n", startReq.ClusterId)
+			return nil
+		}
+
+		return err
+	}
+}
+
 func init() {
 	listOverrides = append(listOverrides, listOverride)
 	listNodeTypesOverrides = append(listNodeTypesOverrides, listNodeTypesOverride)
 	sparkVersionsOverrides = append(sparkVersionsOverrides, sparkVersionsOverride)
+	startOverrides = append(startOverrides, startOverride)
 }
diff --git a/cmd/workspace/clusters/overrides_test.go b/cmd/workspace/clusters/overrides_test.go
new file mode 100644
index 00000000000..f717c4c3952
--- /dev/null
+++ b/cmd/workspace/clusters/overrides_test.go
@@ -0,0 +1,45 @@
+package clusters
+
+import (
+	"bytes"
+	"errors"
+	"testing"
+
+	"github.com/databricks/databricks-sdk-go/apierr"
+	"github.com/databricks/databricks-sdk-go/service/compute"
+	"github.com/spf13/cobra"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestStartOverride_SwallowsInvalidStateError(t *testing.T) {
+	startReq := &compute.StartCluster{ClusterId: "1234-000000-abcdefg"}
+	cmd := &cobra.Command{}
+	cmd.RunE = func(cmd *cobra.Command, args []string) error {
+		return &apierr.APIError{ErrorCode: "INVALID_STATE", Message: "Cluster is in unexpected state Running."}
+	}
+
+	startOverride(cmd, startReq)
+
+	var out bytes.Buffer
+	cmd.SetOut(&out)
+	err := cmd.RunE(cmd, nil)
+
+	require.NoError(t, err)
+	assert.Contains(t, out.String(), startReq.ClusterId)
+}
+
+func TestStartOverride_PropagatesOtherErrors(t *testing.T) {
+	startReq := &compute.StartCluster{ClusterId: "1234-000000-abcdefg"}
+	cmd := &cobra.Command{}
+	wantErr := errors.New("boom")
+	cmd.RunE = func(cmd *cobra.Command, args []string) error {
+		return wantErr
+	}
+
+	startOverride(cmd, startReq)
+
+	err := cmd.RunE(cmd, nil)
+
+	assert.Equal(t, wantErr, err)
+}