[MelbourneDeveloper]

TLDR

Completes Razor support (#397): Razor Pages and MVC views, F# symbols in Razor, the editing features (selection, code actions, hints, lenses, hierarchy), collocated .razor.css/.razor.js files, Blazor WebAssembly debugging and Razor Hot Reload.

Closes #397

Details

Razor Pages and MVC ([RAZOR-MVC])

• Tag helper scope from @addTagHelper/@removeTagHelper/@tagHelperPrefix and _ViewImports.cshtml (RazorTagHelperScope.cs); tag helper elements and attributes hover, define and complete, each once beside the HTML service's items (razor-html.ts de-duplicates by label).
• Attribute facts come from the compiler's IR, with each attribute's end (RazorIr.Attributes.cs, MarkupAttribute.End).

F# in Razor solutions ([RAZOR-FSHARP], [DEFINITION-CROSSLANG-IDENTITY], [REFERENCES-CROSS-LANGUAGE])

• The C# sidecar names an F# project's symbol by assembly and XML doc signature (FSharpProjectSymbols.cs) and reads the built DLL with its XML docs, so hover shows F# /// comments.
• New host module cross_language.rs: a decompiled F# location is replaced by its F# declaration (workspace/declarationForeign), and references merge both sides' uses (workspace/referencesForeign). An answer the F# sidecar cannot place yet is not cached.
• F# side: FSharpForeignSymbols.fs; F# references now sit on the name of a dotted use (player.Score).

Editing features from Razor positions

• Selection ranges ([RAZOR-FEATURES-SELECTION]): RazorSelectionRanges.cs, host razor::handle_selection_ranges (was []).
• Code actions ([RAZOR-CODE-ACTIONS]): add @using, generate an event handler, extract a block to code-behind, extract elements to a new component (RazorQuickFixes.cs, RazorExtractActions.cs). New files arrive as LSP CreateFile operations (code_actions.rs).
• Inlay hints, code lens, call and type hierarchy ([RAZOR-FEATURES-INLAY-HINTS], [RAZOR-FEATURES-CODE-LENS], [RAZOR-FEATURES-HIERARCHY]). Markup callers are the component, named by its file. The C# sidecar's hierarchy kinds are now PascalCase, as the host maps them (they reached clients as the wrong SymbolKind).

Collocated files ([RAZOR-COLLOCATION])

• .razor.css classes complete as LSP Value items inside a class value and define to every selector (CssTokenizer.cs, a CSS Syntax Level 3 tokenizer, and RazorStylesheet.cs). The attribute at the caret is read by the HTML tokenizer (HtmlMarkupContext.Attributes.cs).
• A module literal in InvokeAsync<IJSObjectReference>("import", "…") defines to its .razor.js, from Razor, a code-behind or plain C#.
• VS Code configurationDefaults nest a component's .cs/.css/.js under it. Paths go through NativePaths.StylesheetOf/FromModulePath.

Blazor WebAssembly debugging ([DEBUG-FEATURES-LAUNCH-BLAZOR-WASM])

• New sharplsp-blazorwasm debugger (blazor-wasm-debug.ts, blazor-wasm-launch.ts): runs dotnet run, expands the profile's inspectUri onto the announced address, hands the app to js-debug, and stops the app with the browser session. It declares no languages, so the F5 auto-pick stays sharplsp-coreclr.

Razor Hot Reload ([RAZOR-HOT-RELOAD])

• A Razor save swaps the additional document in every framework copy, and the signature guard judges the generated projections (HotReloadSession.cs). The guard now ignores all trivia, because doc-comment edits were refused as rude edits.
• A re-save of committed text answered notCompilable ("save again" forever). Roslyn reports Status None with nothing pending, so it now answers applied with no deltas, for .cs saves too.
• VS Code's two save paths take the Razor language ids.

Specs and plan: RAZOR-SPEC gains the sections above and loses its "Not Yet Supported" list. DEFINITION/REFERENCES/RENAME/DEBUGGING specs cover the cross-language identity and the WebAssembly debugger. Every RAZOR-PLAN item is checked, with test evidence.

No new dependencies.

How Do The Automated Tests Prove It Works?

Host end-to-end (real sidecars, real fixture solution)

• test_full_stack_razor_pages_and_mvc_views: @model/@inject hover, @functions definition, <input> and asp-for from tag helpers, partial/environment and asp-page (kind 10) completions, and Index.cshtml resolving @model through _ViewImports.cshtml with no errors.
• test_full_stack_fsharp_in_razor_session: F# record hover with its docs, definition into Scores.fs, references with and without the declaration, and rename from Razor and from F#. Its workspace now builds the F# library, because C# reads only a built DLL.
• test_full_stack_razor_selection_ranges, test_full_stack_razor_hierarchy_and_hints: exact nested chains, and hierarchy items and LSP kinds.
• test_full_stack_razor_collocated_styles_and_scripts: five .title selectors, each ranged on the name; module definition at Card.razor.js 0:0 from @code and plain C#; title completes once as kind 12, replacing only ti.
• test_cross_language_definition_csharp_to_fsharp now also asserts a C# local's references stay in C# once the F# sidecar is loaded.
• Full host suite locally: 580/580.

Sidecar (C# 803/803, F# 457/457, Common 125/125)

• RazorMvcTests, RazorFSharpTests, RazorSelectionRangesTests, RazorCodeActionsTests (including whitespace-trimmed, dedented extraction, and refusal when an outside local is captured), RazorHintsAndLensesTests, RazorHierarchyTests, CallHierarchyKindTests.
• RazorCollocationTests, RazorStylesheetTests, and HtmlMarkupContextTests for the attribute at a caret. The last caught three bugs, each failing first: a bare attribute before class, a caret on a name, a caret after a value.
• RazorHotReloadTests (5): markup and @code body edits emit real deltas; a mixed .cs+Razor batch applies as one; an @code signature change is restartRequired naming the method; an unlisted file is refused by name. Each fails with the Razor branch disabled. HotReloadSessionRegistryTests asserts the quiet .cs re-save leaves nothing to commit.
• RazorSidecarTests drives textDocument/selectionRange and workspace/referencesForeign over the real socket. FSharpForeignSymbolsTests and FSharpForeignSymbolsWireTests cover declarations, uses and the wire handlers.

VS Code

• razor-lsp.test.ts: F# navigation, references and rename from Razor; a Razor Page completes tag helpers once; stylesheet class definition and completion, and the nesting defaults VS Code applies.
• blazor-wasm-debug.test.ts (a real dotnet run of the WebAssembly fixture) and blazor-wasm-debug-resolution.test.ts (profiles, inspectUri, run arguments, the app stopped with the session, a browser that never starts, an app that dies during the handoff).
• debug-hot-reload-e2e.test.ts: a saved .razor reaches the sidecar and is refused by name, and the session survives. fsi-build-output-e2e.test.ts covers the dotnet watch path.
• Locally: razor 9, debug 58, hot reload 16 passing.

Coverage of changed lines (local): C# 2005/2079 before the review's added tests, with the project at 96.5%; F# 100/101; Common 19/19; host 441/447; new WebAssembly files 887/911 (97.4%). What stays uncovered is the real js-debug handoff, the 180 s startup timer and some unreachable catch arms.