introduce attribute and nesting validation + lsp features

This commit introduces an entirely new system that validates attributes
and element nesting, alongside all the major features expected by a
language server.

Note that all new validation is not compatible with templating languages,
support for that will be explored in the near future, but for now this is
strictly for vanilla html (validation is disabled entirely for SuperHTML
templates at the moment as well).

All of this code is considered experimental so if you build superhtml
from this commit, be warned that you will probably encounter bugs, but
beta testing is appreciated at this stage.

If you want to report a bug, please take a good read at the Issue
templates, as I'm asking submitters to provide a reference to the HTML
spec section that the bug pertains to, in order to minimize the amount
of bad issues that complain about correct -- but maybe lesser known
-- errors.

On the front of the language server, we now provide:
- diagnostics for all kinds of errors
- autocomplete for element names, attribute names, and attribute values
- symbol rename on element names to change both tags at once
- linked edits to achieve the same as above (when supported by the
  editor, see #74)
- duplicate class name warnings
- find all references for class names
- descriptions for all elements, attributes and attribute values of
  enumerated attributes (i.e. attributes whose values are options in a
  list).

The autoformatter uses now a new formatting layout where the first
attribute is kept on the same line as the element name.

Additionally, the autoformatter now uses tabs for indentation and spaces
for alignment. This is also experimental and might be reverted in the
future.

Author: kristoff-it

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,4 @@
+contact_links:
+  - name: WHATWG Living HTML Specification
+    about: "If you are reporting a problem relative to HTML diagnostics you will need to provide a referece to the WHATWG Living HTML specification that points out the discrepancy".
+    url: https://html.spec.whatwg.org/multipage/

.github/ISSUE_TEMPLATE/crash.yml

@@ -0,0 +1,28 @@
+name: Crash / Hang Report
+description: Report SuperHTML crashing or hanging. 
+labels: ["crash/hang"]
+body:
+  - type: input
+    id: version
+    attributes:
+      label: SuperHTML Version
+      description: "The output of `superhtml version` (or the VSCode extension version)"
+      placeholder: "v0.5.3-dev.59+0336596"
+    validations:
+      required: true
+  - type: input
+    id: platform
+    attributes:
+      label: OS and Editor (if any)
+      description: "Which OS and which editor (if reporting a LSP crash/hang) are you using?"
+      placeholder: "Linux, helix"
+    validations:
+      required: true
+  - type: markdown
+    id: repro
+    attributes:
+      label: Steps to Reproduce and Observed Behavior
+      description: What exactly can someone else do, in order to observe the problem that you observed? Include error messages, if any.
+    validations:
+      required: true
+

.github/ISSUE_TEMPLATE/error_message.yml

@@ -0,0 +1,26 @@
+name: Missing or Wrong HTML diagnostic
+description: Report an error with how SuperHTML validates HTML.
+labels: ["diagnostic"]
+body:
+  - type: input
+    id: version
+    attributes:
+      label: SuperHTML Version
+      description: "The output of `superhtml version` (or the VSCode extension version)"
+      placeholder: "v0.5.3-dev.59+0336596"
+    validations:
+      required: true
+  - type: markdown
+    id: repro
+    attributes:
+      label: Steps to Reproduce and Observed Behavior
+      description: What exactly can someone else do, in order to observe the problem that you observed? Include error messages, if any.
+    validations:
+      required: true
+  - type: markdown
+    id: expected
+    attributes:
+      label: Expected Output according to the HTML spec
+      description: "NOTE: failing to provide a quote from the WHATWG HTML living specification that shows the discrepancy might cause your issue to be closed without any explanation."
+    validations:
+      required: true

build.zig

@@ -64,14 +64,6 @@ pub fn build(b: *std.Build) !void {
     if (version == .tag) {
         setupReleaseStep(b, options, superhtml, folders, lsp);
     }
-
-    if (b.option(
-        bool,
-        "fuzz",
-        "Generate an executable for AFL++ (persistent mode) plus extra tooling",
-    ) orelse false) {
-        setupFuzzStep(b, target, superhtml);
-    }
 }
 
 fn setupCheckStep(
@@ -137,61 +129,6 @@ fn setupTestStep(
     test_step.dependOn(&run_fuzz_tests.step);
 }
 
-fn setupFuzzStep(
-    b: *std.Build,
-    target: std.Build.ResolvedTarget,
-    superhtml: *std.Build.Module,
-) void {
-    const afl = b.lazyImport(@This(), "afl_kit") orelse return;
-    const afl_obj = b.addObject(.{
-        .name = "superfuzz-afl",
-        .root_module = b.createModule(.{
-            .root_source_file = b.path("src/fuzz/afl.zig"),
-            .target = target,
-            .optimize = .ReleaseSafe,
-        }),
-    });
-
-    afl_obj.root_module.addImport("superhtml", superhtml);
-    afl_obj.root_module.stack_check = false; // not linking with compiler-rt
-    afl_obj.root_module.link_libc = true; // afl runtime depends on libc
-
-    const afl_fuzz = afl.addInstrumentedExe(
-        b,
-        target,
-        .ReleaseSafe,
-        null,
-        false,
-        afl_obj,
-    ) orelse return;
-    b.getInstallStep().dependOn(&b.addInstallFile(afl_fuzz, "superfuzz-afl").step);
-    // b.installArtifact(afl_fuzz);
-
-    const super_fuzz = b.addExecutable(.{
-        .name = "superfuzz",
-        .root_module = b.createModule(.{
-            .root_source_file = b.path("src/fuzz.zig"),
-            .target = target,
-            .optimize = .ReleaseSafe,
-        }),
-    });
-
-    super_fuzz.root_module.addImport("superhtml", superhtml);
-    b.installArtifact(super_fuzz);
-
-    const supergen = b.addExecutable(.{
-        .name = "supergen",
-        .root_module = b.createModule(.{
-            .root_source_file = b.path("src/fuzz/astgen.zig"),
-            .target = target,
-            .optimize = .Debug,
-        }),
-    });
-
-    supergen.root_module.addImport("superhtml", superhtml);
-    b.installArtifact(supergen);
-}
-
 fn setupCliTool(
     b: *std.Build,
     target: std.Build.ResolvedTarget,

build.zig.zon

@@ -2,13 +2,8 @@
     .name = .superhtml,
     .version = "0.4.0",
     .fingerprint = 0xc5e9aede3c1db363,
-    .minimum_zig_version = "0.15.0",
+    .minimum_zig_version = "0.15.1",
     .dependencies = .{
-        .afl_kit = .{
-            .url = "git+https://github.com/kristoff-it/zig-afl-kit#8ef04d1db48650345dca68da1e1b8f2615125c40",
-            .hash = "afl_kit-0.1.0-NdJ3cvscAACLEvjZTB017IAks_Uq5ux1qpA-klDe384Y",
-            .lazy = true,
-        },
         .known_folders = .{
             .url = "git+https://github.com/ziglibs/known-folders#ab5cf5feb936fa3b72c95d3ad0c0c67791937ba1",
             .hash = "known_folders-0.0.0-Fy-PJtTTAADUOhGKM0sxzG4eMkNQxRvx9e5dfHVyaeA3",

editors/vscode/.vscode/test.html

@@ -1,16 +1,14 @@
 <!DOCTYPE html>
 
 <html>
-<title>
-    << /title>
-
-        <head>
-        </head>
-
-        <body id id>
-            <p>
-                << /p>
-        </body>
-
+<title></title>
+<div />
+<p>
+
+    foo
+</p>
+<foo></foo>
+</div>
+</span>
 
 </html>

src/cli.zig

@@ -30,24 +30,28 @@ pub fn panic(
     ret_addr: ?usize,
 ) noreturn {
     if (lsp_mode) {
-        std.log.err("{s}\n\n{?f}", .{ msg, trace });
+        std.log.err("\n{s}\n\n{?f}", .{ msg, trace });
     } else {
-        std.debug.print("{s}\n\n{?f}", .{ msg, trace });
+        std.debug.print("\n{s}\n\n{?f}", .{ msg, trace });
     }
     blk: {
         const out: std.fs.File = if (!lsp_mode) std.fs.File.stderr() else logging.log_file orelse break :blk;
         var writer = out.writerStreaming(&.{});
         const w = &writer.interface;
+        w.print("\n{s}\n\n{?f}", .{ msg, trace }) catch {};
         if (builtin.strip_debug_info) {
-            w.print("Unable to dump stack trace: debug info stripped\n", .{}) catch return;
+            w.print("Unable to dump stack trace: debug info stripped\n", .{}) catch {};
             break :blk;
         }
         const debug_info = std.debug.getSelfDebugInfo() catch |err| {
-            w.print("Unable to dump stack trace: Unable to open debug info: {s}\n", .{@errorName(err)}) catch break :blk;
+            w.print(
+                "Unable to dump stack trace: Unable to open debug info: {s}\n",
+                .{@errorName(err)},
+            ) catch {};
             break :blk;
         };
         std.debug.writeCurrentStackTrace(w, debug_info, .no_color, ret_addr) catch |err| {
-            w.print("Unable to dump stack trace: {t}\n", .{err}) catch break :blk;
+            w.print("Unable to dump stack trace: {t}\n", .{err}) catch {};
             break :blk;
         };
     }

src/cli/logging.zig

@@ -22,7 +22,10 @@ pub fn logFn(
     comptime format: []const u8,
     args: anytype,
 ) void {
-    // if (scope != .srcset) return;
+    // switch (scope) {
+    //     .root, .super_lsp, .@"html/ast" => {},
+    //     else => return,
+    // }
     inline for (build_options.enabled_scopes) |es| {
         if (comptime std.mem.eql(u8, es, @tagName(scope))) {
             break;

src/cli/lsp.zig

@@ -125,7 +125,7 @@ pub fn initialize(
             .triggerCharacters = &.{
                 "<",  "/", " ",
                 "\n", "'", "\"",
-                "=",
+                "=",  ",",
             },
         },
 
@@ -242,7 +242,7 @@ pub fn @"textDocument/formatting"(
     log.debug("format request!!", .{});
 
     const doc = self.files.getPtr(request.textDocument.uri) orelse return null;
-    if (doc.html.errors.len != 0) {
+    if (doc.html.has_syntax_errors) {
         return null;
     }
 
@@ -514,13 +514,14 @@ pub fn @"textDocument/completion"(
         self.offset_encoding,
     );
 
-    log.debug("===== lsp autocomplete!", .{});
+    log.debug("===== lsp autocomplete! offset={}", .{offset});
 
     const completions = try doc.html.completions(arena, doc.src, @intCast(offset));
     const items = try arena.alloc(lsp.types.CompletionItem, completions.len);
     for (items, completions) |*it, cpl| {
         it.* = .{
             .label = cpl.label,
+            .insertText = cpl.value,
             .documentation = if (cpl.desc.len == 0) null else .{
                 .MarkupContent = .{
                     .kind = .markdown,

src/cli/lsp/logic.zig

@@ -48,12 +48,27 @@ pub fn loadFile(
             const range = getRange(err.main_location, doc.src);
             d.* = .{
                 .range = range,
-                .severity = .Error,
+                .severity = switch (err.tag) {
+                    .unsupported_doctype, .duplicate_class => .Warning,
+                    else => .Error,
+                },
                 .message = try std.fmt.allocPrint(arena, "{f}", .{err.tag.fmt(doc.src)}),
                 .code = .{ .string = @tagName(err.tag) },
                 .source = if (err.tag == .token) "html tokenizer" else "html parser",
                 .relatedInformation = switch (err.tag) {
                     else => null,
+                    .duplicate_class => |span| try arena.dupe(
+                        lsp.types.DiagnosticRelatedInformation,
+                        &.{
+                            .{
+                                .location = .{ .uri = uri, .range = getRange(
+                                    span,
+                                    doc.src,
+                                ) },
+                                .message = "original",
+                            },
+                        },
+                    ),
                     .duplicate_attribute_name => |span| try arena.dupe(
                         lsp.types.DiagnosticRelatedInformation,
                         &.{