From de26f3b88c302ca1c4d85256af5e96c7e73f02e8 Mon Sep 17 00:00:00 2001
From: ross-p-smith <rosmith@microsoft.com>
Date: Thu, 29 Jan 2026 22:22:25 +0000
Subject: [PATCH] Added BUILDKIT_INLINE_CACHE for containerFeature path

---
 src/spec-node/containerFeatures.ts | 5 ++++-
 src/spec-node/singleContainer.ts   | 6 ++++--
 src/spec-node/utils.ts             | 7 +++++++
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/src/spec-node/containerFeatures.ts b/src/spec-node/containerFeatures.ts
index cc957c592..e05822d1b 100644
--- a/src/spec-node/containerFeatures.ts
+++ b/src/spec-node/containerFeatures.ts
@@ -11,7 +11,7 @@ import { LogLevel, makeLog } from '../spec-utils/log';
 import { FeaturesConfig, getContainerFeaturesBaseDockerFile, getFeatureInstallWrapperScript, getFeatureLayers, getFeatureMainValue, getFeatureValueObject, generateFeaturesConfig, Feature, generateContainerEnvs } from '../spec-configuration/containerFeaturesConfiguration';
 import { readLocalFile } from '../spec-utils/pfs';
 import { includeAllConfiguredFeatures } from '../spec-utils/product';
-import { createFeaturesTempFolder, DockerResolverParameters, getCacheFolder, getFolderImageName, getEmptyContextFolder, SubstitutedConfig } from './utils';
+import { createFeaturesTempFolder, DockerResolverParameters, getCacheFolder, getFolderImageName, getEmptyContextFolder, SubstitutedConfig, isBuildxCacheToInline } from './utils';
 import { isEarlierVersion, parseVersion, runCommandNoPty } from '../spec-common/commonUtils';
 import { getDevcontainerMetadata, getDevcontainerMetadataLabel, getImageBuildInfoFromImage, ImageBuildInfo, ImageMetadataEntry, imageMetadataLabel, MergedDevContainerConfig } from './imageMetadata';
 import { supportsBuildContexts } from './dockerfileUtils';
@@ -85,6 +85,9 @@ export async function extendImage(params: DockerResolverParameters, config: Subs
 		if (params.buildxCacheTo) {
 			args.push('--cache-to', params.buildxCacheTo);
 		}
+		if (!isBuildxCacheToInline(params.buildxCacheTo)) {
+			args.push('--build-arg', 'BUILDKIT_INLINE_CACHE=1');
+		}
 		if (!params.buildNoCache) {
 			params.additionalCacheFroms.forEach(cacheFrom => args.push('--cache-from', cacheFrom));
 		}
diff --git a/src/spec-node/singleContainer.ts b/src/spec-node/singleContainer.ts
index 2f4a8a3fc..dc38ef1fc 100644
--- a/src/spec-node/singleContainer.ts
+++ b/src/spec-node/singleContainer.ts
@@ -4,7 +4,7 @@
  *--------------------------------------------------------------------------------------------*/
 
 
-import { createContainerProperties, startEventSeen, ResolverResult, getTunnelInformation, getDockerfilePath, getDockerContextPath, DockerResolverParameters, isDockerFileConfig, uriToWSLFsPath, WorkspaceConfiguration, getFolderImageName, inspectDockerImage, logUMask, SubstitutedConfig, checkDockerSupportForGPU, isBuildKitImagePolicyError } from './utils';
+import { createContainerProperties, startEventSeen, ResolverResult, getTunnelInformation, getDockerfilePath, getDockerContextPath, DockerResolverParameters, isDockerFileConfig, uriToWSLFsPath, WorkspaceConfiguration, getFolderImageName, inspectDockerImage, logUMask, SubstitutedConfig, checkDockerSupportForGPU, isBuildKitImagePolicyError, isBuildxCacheToInline } from './utils';
 import { ContainerProperties, setupInContainer, ResolverProgress, ResolverParameters } from '../spec-common/injectHeadless';
 import { ContainerError, toErrorText } from '../spec-common/errors';
 import { ContainerDetails, listContainers, DockerCLIParameters, inspectContainers, dockerCLI, dockerPtyCLI, toPtyExecParameters, ImageDetails, toExecParameters, removeContainer } from '../spec-shutdown/dockerUtils';
@@ -209,7 +209,9 @@ async function buildAndExtendImage(buildParams: DockerResolverParameters, config
 		if (buildParams.buildxCacheTo) {
 			args.push('--cache-to', buildParams.buildxCacheTo);
 		}
-		args.push('--build-arg', 'BUILDKIT_INLINE_CACHE=1');
+		if (!isBuildxCacheToInline(buildParams.buildxCacheTo)) {
+			args.push('--build-arg', 'BUILDKIT_INLINE_CACHE=1');
+		}
 	} else {
 		args.push('build');
 	}
diff --git a/src/spec-node/utils.ts b/src/spec-node/utils.ts
index 1fb1ec1cc..5c0fb374c 100644
--- a/src/spec-node/utils.ts
+++ b/src/spec-node/utils.ts
@@ -93,6 +93,13 @@ export async function logUMask(params: DockerResolverParameters): Promise<string
 	}
 }
 
+export function isBuildxCacheToInline(buildxCacheTo: string | undefined): boolean {
+	if (!buildxCacheTo) {
+		return false;
+	}
+	return /type\s*=\s*inline/i.test(buildxCacheTo);
+}
+
 export type ParsedAuthority = DevContainerAuthority;
 
 export type UpdateRemoteUserUIDDefault = 'never' | 'on' | 'off';