cmd/roachtest: fix stage 'latest'

Previously we would change it to '' to pass it to Stage() but this meant
validation of binary types saw an empty arg and assumed we were not staging,
and thus still validated local binaries. Instead, leave the flag along and
just zero a copy for passing to Stage().

Release note: none.
Epic: none.

Author: dt

pkg/cmd/roachtest/cluster.go

@@ -325,7 +325,10 @@ func initBinariesAndLibraries() {
 	cockroachPath := roachtestflags.CockroachPath
 	cockroachEAPath := roachtestflags.CockroachEAPath
 	workloadPath := roachtestflags.WorkloadPath
-	cockroach[defaultArch], _ = resolveBinary("cockroach", cockroachPath, defaultArch, true, false)
+	// Skip cockroach binary validation if using --cockroach-stage
+	if roachtestflags.CockroachStage == "" {
+		cockroach[defaultArch], _ = resolveBinary("cockroach", cockroachPath, defaultArch, true, false)
+	}
 	// Let the test runner verify the workload binary exists if TestSpec.RequiresDeprecatedWorkload is true.
 	workload[defaultArch], _ = resolveBinary("workload", workloadPath, defaultArch, false, false)
 	cockroachEA[defaultArch], err = resolveBinary("cockroach-ea", cockroachEAPath, defaultArch, false, true)
@@ -336,7 +339,9 @@ func initBinariesAndLibraries() {
 	if roachtestflags.ARM64Probability > 0 && defaultArch != vm.ArchARM64 {
 		fmt.Printf("Locating and verifying binaries for os=%q, arch=%q\n", defaultOSName, vm.ArchARM64)
 		// We need to verify we have all the required binaries for arm64.
-		cockroach[vm.ArchARM64], _ = resolveBinary("cockroach", cockroachPath, vm.ArchARM64, true, false)
+		if roachtestflags.CockroachStage == "" {
+			cockroach[vm.ArchARM64], _ = resolveBinary("cockroach", cockroachPath, vm.ArchARM64, true, false)
+		}
 		workload[vm.ArchARM64], _ = resolveBinary("workload", workloadPath, vm.ArchARM64, true, false)
 		cockroachEA[vm.ArchARM64], err = resolveBinary("cockroach-ea", cockroachEAPath, vm.ArchARM64, false, true)
 		if err != nil {
@@ -346,7 +351,9 @@ func initBinariesAndLibraries() {
 	if roachtestflags.FIPSProbability > 0 && defaultArch != vm.ArchFIPS {
 		fmt.Printf("Locating and verifying binaries for os=%q, arch=%q\n", defaultOSName, vm.ArchFIPS)
 		// We need to verify we have all the required binaries for fips.
-		cockroach[vm.ArchFIPS], _ = resolveBinary("cockroach", cockroachPath, vm.ArchFIPS, true, false)
+		if roachtestflags.CockroachStage == "" {
+			cockroach[vm.ArchFIPS], _ = resolveBinary("cockroach", cockroachPath, vm.ArchFIPS, true, false)
+		}
 		workload[vm.ArchFIPS], _ = resolveBinary("workload", workloadPath, vm.ArchFIPS, true, false)
 		cockroachEA[vm.ArchFIPS], err = resolveBinary("cockroach-ea", cockroachEAPath, vm.ArchFIPS, false, true)
 		if err != nil {
@@ -1939,7 +1946,11 @@ func (c *clusterImpl) PutE(
 func (c *clusterImpl) PutCockroach(ctx context.Context, l *logger.Logger, t *testImpl) error {
 	if roachtestflags.CockroachStage != "" {
 		// Use staging instead of upload when --cockroach-stage is specified
-		return c.Stage(ctx, l, "cockroach", roachtestflags.CockroachStage, ".", c.All())
+		stageVersion := roachtestflags.CockroachStage
+		if stageVersion == "latest" {
+			stageVersion = "" // Stage() expects empty string for latest
+		}
+		return c.Stage(ctx, l, "cockroach", stageVersion, ".", c.All())
 	}
 	return c.PutE(ctx, l, t.Cockroach(), test.DefaultCockroachPath, c.All())
 }

pkg/cmd/roachtest/main.go

@@ -581,8 +581,4 @@ func validateAndConfigure(cmd *cobra.Command, args []string) {
 		printErrAndExit(fmt.Errorf("--cockroach and --cockroach-stage are mutually exclusive. Use one or the other"))
 	}
 
-	// Normalize "latest" to empty string for staging system
-	if roachtestflags.CockroachStage == "latest" {
-		roachtestflags.CockroachStage = ""
-	}
 }