feat(lsp): pull diagnostics, include links and folding ranges

Assisted-by: GLM 5.3 Flash

lsp/handlers.go

@@ -5,6 +5,10 @@ package lsp
 
 import (
 	"fmt"
+	"os"
+	"path/filepath"
+	"regexp"
+	"runtime"
 	"sort"
 	"strings"
 	"unicode"
@@ -13,6 +17,7 @@ import (
 	"sourcedock.dev/petrbalvin/gasm-devkit/ast"
 	"sourcedock.dev/petrbalvin/gasm-devkit/format"
 	"sourcedock.dev/petrbalvin/gasm-devkit/lexer"
+	"sourcedock.dev/petrbalvin/gasm-devkit/lint"
 	"sourcedock.dev/petrbalvin/gasm-devkit/parser"
 	"sourcedock.dev/petrbalvin/gasm-devkit/token"
 )
@@ -784,3 +789,94 @@ func textRange(t *ast.Text) Range {
 	}
 	return Range{Start: start, End: end}
 }
+
+// diagnosticsFor computes the LSP diagnostics of one document; the push
+// (publishDiagnostics) and pull (textDocument/diagnostic) paths share it.
+func (s *Server) diagnosticsFor(uri string) []Diagnostic {
+	text := s.docs[uri]
+	f, _ := parser.Parse(uriPath(uri), text)
+	cfg := lint.Config{Arch: arch.FromFilename(uriPath(uri))}
+	diags := lint.File(f, cfg)
+
+	out := make([]Diagnostic, 0, len(diags))
+	for _, d := range diags {
+		out = append(out, Diagnostic{
+			Range:    toRange(d.Pos.Line, d.Pos.Column, d.End),
+			Severity: lintSeverity(d.Severity),
+			Code:     d.Code,
+			Source:   "gasm",
+			Message:  d.Message,
+		})
+	}
+	return out
+}
+
+// includeRe matches a #include directive's quoted path.
+var includeRe = regexp.MustCompile(`^\s*#include\s+"([^"]+)"`)
+
+// documentLinks links each #include path to the header file it resolves to:
+// first relative to the document's directory, then in $GOROOT/pkg/include
+// (where textflag.h and friends live).  Unresolvable paths get no link.
+func (s *Server) documentLinks(uri string) []DocumentLink {
+	text := s.docs[uri]
+	if text == "" {
+		return nil
+	}
+	docDir := filepath.Dir(uriPath(uri))
+	goroot := runtime.GOROOT()
+
+	var out []DocumentLink
+	for i, line := range strings.Split(text, "\n") {
+		m := includeRe.FindStringSubmatch(line)
+		if m == nil {
+			continue
+		}
+		target := resolveInclude(docDir, goroot, m[1])
+		if target == "" {
+			continue
+		}
+		start := strings.Index(line, "\"")
+		out = append(out, DocumentLink{
+			Range: Range{
+				Start: Position{Line: i, Character: start},
+				End:   Position{Line: i, Character: start + len(m[1]) + 2},
+			},
+			Target: "file://" + target,
+		})
+	}
+	return out
+}
+
+// resolveInclude returns the existing file a #include path refers to, or "".
+func resolveInclude(docDir, goroot, path string) string {
+	for _, dir := range []string{docDir, filepath.Join(goroot, "pkg", "include")} {
+		cand := filepath.Join(dir, path)
+		if _, err := os.Stat(cand); err == nil {
+			return cand
+		}
+	}
+	return ""
+}
+
+// foldingRanges marks each TEXT function's body as a collapsible region.
+func (s *Server) foldingRanges(uri string) []FoldingRange {
+	text := s.docs[uri]
+	f, _ := parser.Parse(uriPath(uri), text)
+	if f == nil {
+		return nil
+	}
+	var out []FoldingRange
+	for _, d := range f.Decls {
+		t, ok := d.(*ast.Text)
+		if !ok || len(t.Body) == 0 {
+			continue
+		}
+		start := t.Keyword.Pos.Line - 1
+		end := t.Body[len(t.Body)-1].Pos().Line - 1
+		if end <= start {
+			continue
+		}
+		out = append(out, FoldingRange{StartLine: start, EndLine: end, Kind: "region"})
+	}
+	return out
+}