fix(lsp): recover from handler panics and decode client uris

lsp/server_test.go

@@ -381,7 +381,7 @@ func TestCodeActions(t *testing.T) {
 		frame(10, "textDocument/codeAction", map[string]any{
 			"textDocument": map[string]any{"uri": "file:///f_amd64.s"},
 			"range":        map[string]any{"start": map[string]any{"line": 0, "character": 0}, "end": map[string]any{"line": 2, "character": 0}},
-			"context":      map[string]any{"diagnostics": []map[string]any{{"code": "missing-ret", "range": map[string]any{"start": map[string]any{"line": 0, "character": 0}, "end": map[string]any{"line": 0, "character": 4}}}}},
+			"context":      map[string]any{"diagnostics": []map[string]any{{"code": "missing-ret", "range": map[string]any{"start": map[string]any{"line": 1, "character": 0}, "end": map[string]any{"line": 1, "character": 4}}}}},
 		}) + frame(nil, "exit", nil)
 	msgs := run(t, in)
 	resp := findByID(msgs, 10)
@@ -395,8 +395,8 @@ func TestCodeActions(t *testing.T) {
 	if len(actions) == 0 {
 		t.Fatal("want at least 1 code action for missing-ret")
 	}
-	if actions[0].Title != "Add RET" {
-		t.Errorf("action title = %q, want Add RET", actions[0].Title)
+	if actions[0].Title != "Add RET to foo" {
+		t.Errorf("action title = %q, want Add RET to foo", actions[0].Title)
 	}
 }
 
@@ -571,3 +571,123 @@ func TestFoldingRanges(t *testing.T) {
 		t.Errorf("folding kind = %q, want region", ranges[0].Kind)
 	}
 }
+
+// TestInitializeVersion checks the version reported in the initialize
+// result when the caller stamps one.
+func TestInitializeVersion(t *testing.T) {
+	var out bytes.Buffer
+	srv := New(strings.NewReader(frame(1, "initialize", map[string]any{})+frame(nil, "exit", nil)), &out)
+	srv.SetVersion("9.9.9")
+	if err := srv.Run(); err != nil {
+		t.Fatalf("server run: %v", err)
+	}
+	msgs := readFrames(t, &out)
+	resp := findByID(msgs, 1)
+	if resp == nil {
+		t.Fatal("no initialize response")
+	}
+	var res initializeResult
+	if err := json.Unmarshal(mustResult(t, resp), &res); err != nil {
+		t.Fatal(err)
+	}
+	if res.ServerInfo["version"] != "9.9.9" {
+		t.Errorf("serverInfo = %v, want version 9.9.9", res.ServerInfo)
+	}
+}
+
+// TestSyntaxDiagnosticsPublished checks that parse errors reach the editor
+// as error-severity diagnostics with the syntax code.
+func TestSyntaxDiagnosticsPublished(t *testing.T) {
+	msgs := run(t, session("file:///f_amd64.s", "TEXT $\n")+frame(nil, "exit", nil))
+	pub := findMethod(msgs, "textDocument/publishDiagnostics")
+	if pub == nil {
+		t.Fatal("no publishDiagnostics notification")
+	}
+	var p publishDiagnosticsParams
+	json.Unmarshal(pub.Params, &p)
+	found := false
+	for _, d := range p.Diagnostics {
+		if d.Code == "syntax" && d.Severity == sevError {
+			found = true
+		}
+	}
+	if !found {
+		t.Fatalf("expected a syntax error diagnostic, got %+v", p.Diagnostics)
+	}
+}
+
+// TestDispatchRecoversFromPanic exercises the per-message recover: a panic
+// inside a handler is answered as an internal error instead of taking the
+// server down.
+func TestDispatchRecoversFromPanic(t *testing.T) {
+	var out bytes.Buffer
+	srv := New(strings.NewReader(""), &out)
+	srv.docs = nil // force a nil-map write inside didOpen
+	raw := json.RawMessage(`{"textDocument":{"uri":"file:///x.s","text":"RET"}}`)
+	srv.dispatch(&rpcMessage{ID: rawID(t, 7), Method: "textDocument/didOpen", Params: raw})
+	msgs := readFrames(t, &out)
+	resp := findByID(msgs, 7)
+	if resp == nil {
+		t.Fatal("no error response after panic")
+	}
+	if resp.Error == nil || resp.Error.Code != errInternalError {
+		t.Fatalf("error = %+v, want internal error", resp.Error)
+	}
+}
+
+func rawID(t *testing.T, n int) *json.RawMessage {
+	t.Helper()
+	b, err := json.Marshal(n)
+	if err != nil {
+		t.Fatal(err)
+	}
+	raw := json.RawMessage(b)
+	return &raw
+}
+
+// TestURIDecoding pins the percent-decoding of file URIs: clients encode
+// non-ASCII paths, and the decoded form is what resolves on disk.
+func TestURIDecoding(t *testing.T) {
+	got := uriPath("file:///home/petrbalvin/Repozit%C3%A1%C5%99e/k.s")
+	if got != "/home/petrbalvin/Repozitáře/k.s" {
+		t.Errorf("uriPath = %q", got)
+	}
+	if got := uriPath("/plain/path.s"); got != "/plain/path.s" {
+		t.Errorf("uriPath plain = %q", got)
+	}
+}
+
+// TestCodeActionsTargetsFlaggedFunctionOnly checks that a missing-ret
+// diagnostic offers an edit for the flagged function only, even when the
+// file defines several functions.
+func TestCodeActionsTargetsFlaggedFunctionOnly(t *testing.T) {
+	doc := "TEXT \u00b7first(SB), NOSPLIT, $0\n" +
+		"\tMOVQ AX, CX\n" +
+		"\tRET\n" +
+		"TEXT \u00b7second(SB), NOSPLIT, $0\n" +
+		"\tMOVQ AX, CX\n"
+	in := session("file:///f_amd64.s", doc) +
+		frame(11, "textDocument/codeAction", map[string]any{
+			"textDocument": map[string]any{"uri": "file:///f_amd64.s"},
+			"range":        map[string]any{"start": map[string]any{"line": 0, "character": 0}, "end": map[string]any{"line": 4, "character": 0}},
+			"context":      map[string]any{"diagnostics": []map[string]any{{"code": "missing-ret", "range": map[string]any{"start": map[string]any{"line": 3, "character": 0}, "end": map[string]any{"line": 3, "character": 4}}}}},
+		}) + frame(nil, "exit", nil)
+	msgs := run(t, in)
+	resp := findByID(msgs, 11)
+	if resp == nil {
+		t.Fatal("no codeAction response")
+	}
+	var actions []CodeAction
+	if err := json.Unmarshal(mustResult(t, resp), &actions); err != nil {
+		t.Fatal(err)
+	}
+	if len(actions) != 1 {
+		t.Fatalf("actions = %d, want 1", len(actions))
+	}
+	if actions[0].Title != "Add RET to second" {
+		t.Errorf("action title = %q, want Add RET to second", actions[0].Title)
+	}
+	if !strings.Contains(actions[0].Edit.Changes["file:///f_amd64.s"][0].NewText, "\tRET\nTEXT \u00b7second") {
+		t.Errorf("edit does not insert RET at the end of second:\n%s", actions[0].Edit.Changes["file:///f_amd64.s"][0].NewText)
+	}
+}