feat: remy worktree isolation, per-root mutex, parseDiffHunks fix [IDE-2052]

application/di/init.go

@@ -80,6 +80,7 @@ var (
 	scanNotifier                scanner2.ScanNotifier
 	codeActionService           *codeaction.CodeActionsService
 	fileWatcher                 *watcher.FileWatcher
+	remediationNotifier         remediation.FileChangeNotifier
 	initMutex                   = &sync.Mutex{}
 	notifier                    domainNotify.Notifier
 	codeInstrumentor            codeClientObservability.Instrumentor
@@ -108,13 +109,14 @@ type Dependencies struct {
 	// process-lifecycle dependencies used during startup, not per-request.
 	// Access them via di.Installer() / di.Initializer() until those global
 	// accessors are retired.
-	Scanner           scanner2.Scanner
-	HoverService      hover.Service
-	ScanNotifier      scanner2.ScanNotifier
-	ScanPersister     persistence.ScanSnapshotPersister
-	FileWatcher       *watcher.FileWatcher
-	ErrorReporter     er.ErrorReporter
-	CodeActionService *codeaction.CodeActionsService
+	Scanner             scanner2.Scanner
+	HoverService        hover.Service
+	ScanNotifier        scanner2.ScanNotifier
+	ScanPersister       persistence.ScanSnapshotPersister
+	FileWatcher         *watcher.FileWatcher
+	ErrorReporter       er.ErrorReporter
+	CodeActionService   *codeaction.CodeActionsService
+	RemediationNotifier remediation.FileChangeNotifier
 }
 
 func currentDependencies() Dependencies {
@@ -133,13 +135,14 @@ func currentDependencies() Dependencies {
 		InlineValueProvider:   inlineValueProvider,
 		TreeEmitter:           treeEmitterInstance,
 		// Handler-accessed dependencies:
-		Scanner:           scanner,
-		HoverService:      hoverService,
-		ScanNotifier:      scanNotifier,
-		ScanPersister:     scanPersister,
-		FileWatcher:       fileWatcher,
-		ErrorReporter:     errorReporter,
-		CodeActionService: codeActionService,
+		Scanner:             scanner,
+		HoverService:        hoverService,
+		ScanNotifier:        scanNotifier,
+		ScanPersister:       scanPersister,
+		FileWatcher:         fileWatcher,
+		ErrorReporter:       errorReporter,
+		CodeActionService:   codeActionService,
+		RemediationNotifier: remediationNotifier,
 	}
 }
 
@@ -230,12 +233,13 @@ func initApplication(conf configuration.Configuration, engine workflow.Engine, l
 	fileWatcher = watcher.NewFileWatcher()
 
 	var remediationProvider remediation.RemediationProvider
+	remediationNotifier = nil
 	if conf.GetBool(remediationAgentEnabledKey) {
-		lp := engine.GetLogger().With().Str("provider", "remy").Logger()
-		remediationProvider = remediation.NewRemyProvider(remediation.RemyOptions{
-			CliPath: config.GetCliPath(conf),
-			Logger:  &lp,
-		}, nil)
+		p := remediation.NewRemyProvider(engine, nil)
+		remediationProvider = p
+		if n, ok := p.(remediation.FileChangeNotifier); ok {
+			remediationNotifier = n
+		}
 	}
 
 	codeActionService = codeaction.NewService(engine, w, fileWatcher, notifier, featureFlagService, configResolver, remediationProvider)

application/server/server.go

@@ -263,10 +263,14 @@ func initHandlers(srv *jrpc2.Server, handlers handler.Map, conf configuration.Co
 	}
 	handlers["initialize"] = enrich(initializeHandler(conf, engine, srv))
 	handlers["initialized"] = enrich(initializedHandler(conf, engine, srv))
-	handlers["textDocument/didChange"] = enrich(textDocumentDidChangeHandler(conf))
+	var onFileChange func(types.FilePath)
+	if deps.RemediationNotifier != nil {
+		onFileChange = deps.RemediationNotifier.InvalidateFile
+	}
+	handlers["textDocument/didChange"] = enrich(textDocumentDidChangeHandler(conf, onFileChange))
 	handlers["textDocument/didClose"] = enrich(noOpHandler())
 	handlers[textDocumentDidOpenOperation] = enrich(textDocumentDidOpenHandler(conf))
-	handlers[textDocumentDidSaveOperation] = enrich(textDocumentDidSaveHandler(conf))
+	handlers[textDocumentDidSaveOperation] = enrich(textDocumentDidSaveHandler(conf, onFileChange))
 	handlers["textDocument/hover"] = enrich(textDocumentHover())
 	handlers["textDocument/codeAction"] = enrich(textDocumentCodeActionHandler(logger, deps.CodeActionService))
 	handlers["textDocument/codeLens"] = enrich(codeLensHandler())
@@ -501,7 +505,7 @@ func mustConfigResolverFromContext(ctx context.Context) types.ConfigResolverInte
 	return cr
 }
 
-func textDocumentDidChangeHandler(conf configuration.Configuration) jrpc2.Handler {
+func textDocumentDidChangeHandler(conf configuration.Configuration, onFileChange func(types.FilePath)) jrpc2.Handler {
 	return handler.New(func(ctx context.Context, params sglsp.DidChangeTextDocumentParams) (any, error) {
 		logger := ctx2.LoggerFromContext(ctx).With().Str("method", "TextDocumentDidChangeHandler").Logger()
 		pathFromUri := uri.PathFromUri(params.TextDocument.URI)
@@ -519,6 +523,9 @@ func textDocumentDidChangeHandler(conf configuration.Configuration) jrpc2.Handle
 		}
 
 		mustFileWatcherFromContext(ctx).SetFileAsChanged(params.TextDocument.URI)
+		if onFileChange != nil {
+			onFileChange(pathFromUri)
+		}
 
 		return nil, nil
 	})
@@ -1137,7 +1144,7 @@ func textDocumentDidOpenHandler(conf configuration.Configuration) jrpc2.Handler
 	})
 }
 
-func textDocumentDidSaveHandler(conf configuration.Configuration) jrpc2.Handler {
+func textDocumentDidSaveHandler(conf configuration.Configuration, onFileChange func(types.FilePath)) jrpc2.Handler {
 	return handler.New(func(ctx context.Context, params sglsp.DidSaveTextDocumentParams) (any, error) {
 		bgCtx := context.Background()
 		logger := ctx2.LoggerFromContext(ctx).With().Str("method", "TextDocumentDidSaveHandler").Logger()
@@ -1157,6 +1164,10 @@ func textDocumentDidSaveHandler(conf configuration.Configuration) jrpc2.Handler
 			return nil, nil
 		}
 
+		if onFileChange != nil {
+			onFileChange(filePath)
+		}
+
 		if folder.IsAutoScanEnabled() && uri.IsDotSnykFile(params.TextDocument.URI) {
 			go folder.ScanFolder(bgCtx)
 			return nil, nil

domain/snyk/remediation/export_for_test.go

@@ -0,0 +1,25 @@
+/*
+ * © 2026 Snyk Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package remediation
+
+import "github.com/snyk/snyk-ls/internal/types"
+
+// ExportedWorkspaceEditFromContent exposes workspaceEditFromContent for
+// black-box tests in the remediation_test package.
+func ExportedWorkspaceEditFromContent(absPath string, originalContent []byte, diff string) (*types.WorkspaceEdit, error) {
+	return workspaceEditFromContent(absPath, originalContent, diff)
+}

domain/snyk/remediation/provider.go

@@ -42,3 +42,10 @@ type RemediationRequest struct {
 type RemediationProvider interface {
 	Remediate(ctx context.Context, req RemediationRequest) (*types.WorkspaceEdit, error)
 }
+
+// FileChangeNotifier is implemented by providers that cache per-file results.
+// Call InvalidateFile whenever a file is modified so that stale cached diffs
+// are evicted before the user resolves another code action against that file.
+type FileChangeNotifier interface {
+	InvalidateFile(path types.FilePath)
+}