Add @LSP-CALL to file_test (#4896)

Adds @LSP-CALL and refactors LSP keyword handling to implicitly handle a
little more of the LSP structure. This is coming out of textDocument
call handling, where this at least reduces some boilerplate of
`"params": {...}`.

testing/file_test/README.md

@@ -88,6 +88,7 @@ Some keywords can be inserted for content:
 
 -   ```
     [[@LSP:<method>:<extra content>]]
+    [[@LSP-CALL:<method>:<extra content>]]
     [[@LSP-NOTIFY:<method>:<extra content>]]
     [[@LSP-REPLY:<id>:<extra content>]]
     ```
@@ -96,6 +97,25 @@ Some keywords can be inserted for content:
     the `Content-Length` header. The `:<extra content>` is optional, and may be
     omitted.
 
+    The difference between the replacements mirrors LSP calling conventions:
+
+    -   `LSP` does a minimal JSON format, and is primarily intended for testing
+        errors.
+        -   `method`: Assigned from `<method>`.
+    -   `LSP-CALL` maps to
+        [Request Message](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#requestMessage).
+        -   `method`: Assigned from `<method>`.
+        -   `id`: Automatically incremented across calls.
+        -   `params`: Optionally assigned from `<extra content>`.
+    -   `LSP-NOTIFY` maps to
+        [Notification Message](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#notificationMessage).
+        -   `method`: Assigned from `<method>`.
+        -   `params`: Optionally assigned from `<extra content>`.
+    -   `LSP-REPLY` maps to
+        [Response Message](https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#responseMessage).
+        -   `id`: Assigned from `<id>`.
+        -   `result`: Optionally assigned from `<extra content>`.
+
 -   ```
     [[@TEST_NAME]]
     ```

testing/file_test/file_test_base.cpp

@@ -517,62 +517,81 @@ struct SplitState {
   int file_index = 0;
 };
 
-// Reformats `[[@LSP:` and `[[LSP-NOTIFY:` as an LSP call with headers. For
-// notifications, `lsp_call_id` is null.
+// Reformats `[[@LSP:` and similar keyword as an LSP call with headers.
 static auto ReplaceLspKeywordAt(std::string* content, size_t keyword_pos,
-                                int* lsp_call_id, llvm::StringLiteral keyword,
-                                llvm::StringLiteral method_or_id_label)
-    -> ErrorOr<size_t> {
-  auto method_or_id_start = keyword_pos + keyword.size();
+                                int& lsp_call_id) -> ErrorOr<size_t> {
+  llvm::StringRef content_at_keyword =
+      llvm::StringRef(*content).substr(keyword_pos);
+
+  auto [keyword, body_start] = content_at_keyword.split(":");
+  if (body_start.empty()) {
+    return ErrorBuilder() << "Missing `:` for `"
+                          << content_at_keyword.take_front(10) << "`";
+  }
+
+  // Whether the first param is a method or id.
+  llvm::StringRef method_or_id_label = "method";
+  // Whether to attach the `lsp_call_id`.
+  bool use_call_id = false;
+  // The JSON label for extra content.
+  llvm::StringRef extra_content_label;
+  if (keyword == "[[@LSP-CALL") {
+    use_call_id = true;
+    extra_content_label = "params";
+  } else if (keyword == "[[@LSP-NOTIFY") {
+    extra_content_label = "params";
+  } else if (keyword == "[[@LSP-REPLY") {
+    method_or_id_label = "id";
+    extra_content_label = "result";
+  } else if (keyword != "[[@LSP") {
+    return ErrorBuilder() << "Unrecognized @LSP keyword at `"
+                          << keyword.take_front(10) << "`";
+  }
 
   static constexpr llvm::StringLiteral LspEnd = "]]";
-  auto keyword_end = content->find("]]", method_or_id_start);
-  if (keyword_end == std::string::npos) {
+  auto body_end = body_start.find(LspEnd);
+  if (body_end == std::string::npos) {
     return ErrorBuilder() << "Missing `" << LspEnd << "` after `" << keyword
                           << "`";
   }
+  llvm::StringRef body = body_start.take_front(body_end);
+  auto [method_or_id, extra_content] = body.split(":");
 
-  auto method_or_id_end = content->find(":", method_or_id_start);
-  auto extra_content_start = method_or_id_end + 1;
-  if (method_or_id_end == std::string::npos || method_or_id_end > keyword_end) {
-    method_or_id_end = keyword_end;
-    extra_content_start = keyword_end;
+  // Form the JSON.
+  std::string json = llvm::formatv(R"({{"jsonrpc": "2.0", "{0}": "{1}")",
+                                   method_or_id_label, method_or_id);
+  if (use_call_id) {
+    // Omit quotes on the ID because we know it's an integer.
+    json += llvm::formatv(R"(, "id": {0})", ++lsp_call_id);
   }
-  auto method_or_id =
-      llvm::StringRef(*content).slice(method_or_id_start, method_or_id_end);
-
-  auto extra_content =
-      llvm::StringRef(*content).slice(extra_content_start, keyword_end);
-  std::string extra_content_sep;
   if (!extra_content.empty()) {
-    extra_content_sep = ",";
-    if (!extra_content.starts_with("\n")) {
-      extra_content_sep += " ";
+    json += ",";
+    if (extra_content_label.empty()) {
+      if (!extra_content.starts_with("\n")) {
+        json += " ";
+      }
+      json += extra_content;
+    } else {
+      json += llvm::formatv(R"( "{0}": {{{1}})", extra_content_label,
+                            extra_content);
     }
   }
-
-  // Form the JSON.
-  std::string json = R"({"jsonrpc": "2.0", )";
-  if (lsp_call_id) {
-    json += llvm::formatv(R"("id": "{0}", )", ++(*lsp_call_id));
-  }
-  json += llvm::formatv(R"("{0}": "{1}"{2}{3}})", method_or_id_label,
-                        method_or_id, extra_content_sep, extra_content);
+  json += "}";
 
   // Add the Content-Length header. The `2` accounts for extra newlines.
   auto json_with_header =
       llvm::formatv("Content-Length: {0}\n\n{1}\n", json.size() + 2, json)
           .str();
-  // Insert the content.
-  content->replace(keyword_pos, keyword_end + 2 - keyword_pos,
-                   json_with_header);
+  int keyword_len =
+      (body_start.data() + body_end + LspEnd.size()) - keyword.data();
+  content->replace(keyword_pos, keyword_len, json_with_header);
   return keyword_pos + json_with_header.size();
 }
 
 // Replaces the keyword at the given position. Returns the position to start a
 // find for the next keyword.
 static auto ReplaceContentKeywordAt(std::string* content, size_t keyword_pos,
-                                    llvm::StringRef test_name, int* lsp_call_id)
+                                    llvm::StringRef test_name, int& lsp_call_id)
     -> ErrorOr<size_t> {
   auto keyword = llvm::StringRef(*content).substr(keyword_pos);
 
@@ -590,20 +609,8 @@ static auto ReplaceContentKeywordAt(std::string* content, size_t keyword_pos,
     return keyword_pos + test_name.size();
   }
 
-  static constexpr llvm::StringLiteral Lsp = "[[@LSP:";
-  if (keyword.starts_with(Lsp)) {
-    return ReplaceLspKeywordAt(content, keyword_pos, lsp_call_id, Lsp,
-                               "method");
-  }
-  static constexpr llvm::StringLiteral LspNotify = "[[@LSP-NOTIFY:";
-  if (keyword.starts_with(LspNotify)) {
-    return ReplaceLspKeywordAt(content, keyword_pos,
-                               /*lsp_call_id=*/nullptr, LspNotify, "method");
-  }
-  static constexpr llvm::StringLiteral LspReply = "[[@LSP-REPLY:";
-  if (keyword.starts_with(LspReply)) {
-    return ReplaceLspKeywordAt(content, keyword_pos,
-                               /*lsp_call_id=*/nullptr, LspReply, "id");
+  if (keyword.starts_with("[[@LSP")) {
+    return ReplaceLspKeywordAt(content, keyword_pos, lsp_call_id);
   }
 
   return ErrorBuilder() << "Unexpected use of `[[@` at `"
@@ -644,7 +651,7 @@ static auto ReplaceContentKeywords(llvm::StringRef filename,
   while (keyword_pos != std::string::npos) {
     CARBON_ASSIGN_OR_RETURN(
         auto keyword_end,
-        ReplaceContentKeywordAt(content, keyword_pos, test_name, &lsp_call_id));
+        ReplaceContentKeywordAt(content, keyword_pos, test_name, lsp_call_id));
     keyword_pos = content->find(Prefix, keyword_end);
   }
   return Success();

testing/file_test/testdata/lsp_calls.carbon → testing/file_test/testdata/lsp_keywords.carbon

@@ -4,9 +4,9 @@
 
 // AUTOUPDATE
 // TIP: To test this file alone, run:
-// TIP:   bazel test //testing/file_test:file_test_base_test --test_arg=--file_tests=testing/file_test/testdata/lsp_calls.carbon
+// TIP:   bazel test //testing/file_test:file_test_base_test --test_arg=--file_tests=testing/file_test/testdata/lsp_keywords.carbon
 // TIP: To dump output, run:
-// TIP:   bazel run //testing/file_test:file_test_base_test -- --dump_output --file_tests=testing/file_test/testdata/lsp_calls.carbon
+// TIP:   bazel run //testing/file_test:file_test_base_test -- --dump_output --file_tests=testing/file_test/testdata/lsp_keywords.carbon
 
 // --- STDIN
 [[@LSP:foo:]]
@@ -16,6 +16,10 @@
 multi
 line
 ]]
+[[@LSP-CALL:bar:content]]
+[[@LSP-CALL:baz:
+multi
+line]]
 [[@LSP-REPLY:7]]
 [[@LSP-REPLY:8:bar]]
 [[@LSP-NOTIFY:exit]]
@@ -23,32 +27,42 @@ line
 // --- AUTOUPDATE-SPLIT
 
 // CHECK:STDERR: --- STDIN:
-// CHECK:STDERR: Content-Length: 48
+// CHECK:STDERR: Content-Length: 37
 // CHECK:STDERR:
-// CHECK:STDERR: {"jsonrpc": "2.0", "id": "1", "method": "foo"}
+// CHECK:STDERR: {"jsonrpc": "2.0", "method": "foo"}
 // CHECK:STDERR:
-// CHECK:STDERR: Content-Length: 48
+// CHECK:STDERR: Content-Length: 37
 // CHECK:STDERR:
-// CHECK:STDERR: {"jsonrpc": "2.0", "id": "2", "method": "foo"}
+// CHECK:STDERR: {"jsonrpc": "2.0", "method": "foo"}
 // CHECK:STDERR:
-// CHECK:STDERR: Content-Length: 57
+// CHECK:STDERR: Content-Length: 46
 // CHECK:STDERR:
-// CHECK:STDERR: {"jsonrpc": "2.0", "id": "3", "method": "bar", content}
+// CHECK:STDERR: {"jsonrpc": "2.0", "method": "bar", content}
 // CHECK:STDERR:
-// CHECK:STDERR: Content-Length: 61
+// CHECK:STDERR: Content-Length: 50
 // CHECK:STDERR:
-// CHECK:STDERR: {"jsonrpc": "2.0", "id": "4", "method": "baz",
+// CHECK:STDERR: {"jsonrpc": "2.0", "method": "baz",
 // CHECK:STDERR: multi
 // CHECK:STDERR: line
 // CHECK:STDERR: }
 // CHECK:STDERR:
+// CHECK:STDERR: Content-Length: 67
+// CHECK:STDERR:
+// CHECK:STDERR: {"jsonrpc": "2.0", "method": "bar", "id": 1, "params": {content}}
+// CHECK:STDERR:
+// CHECK:STDERR: Content-Length: 71
+// CHECK:STDERR:
+// CHECK:STDERR: {"jsonrpc": "2.0", "method": "baz", "id": 2, "params": {
+// CHECK:STDERR: multi
+// CHECK:STDERR: line}}
+// CHECK:STDERR:
 // CHECK:STDERR: Content-Length: 31
 // CHECK:STDERR:
 // CHECK:STDERR: {"jsonrpc": "2.0", "id": "7"}
 // CHECK:STDERR:
-// CHECK:STDERR: Content-Length: 36
+// CHECK:STDERR: Content-Length: 48
 // CHECK:STDERR:
-// CHECK:STDERR: {"jsonrpc": "2.0", "id": "8", bar}
+// CHECK:STDERR: {"jsonrpc": "2.0", "id": "8", "result": {bar}}
 // CHECK:STDERR:
 // CHECK:STDERR: Content-Length: 38
 // CHECK:STDERR:

toolchain/language_server/testdata/initialize.carbon

@@ -9,15 +9,15 @@
 // TIP:   bazel run //toolchain/testing:file_test -- --dump_output --file_tests=toolchain/language_server/testdata/initialize.carbon
 
 // --- STDIN
-[[@LSP:initialize]]
+[[@LSP-CALL:initialize]]
 [[@LSP-NOTIFY:exit]]
 
 // --- AUTOUPDATE-SPLIT
 
-// CHECK:STDOUT: Content-Length: 148{{\r}}
+// CHECK:STDOUT: Content-Length: 146{{\r}}
 // CHECK:STDOUT: {{\r}}
 // CHECK:STDOUT: {
-// CHECK:STDOUT:   "id": "1",
+// CHECK:STDOUT:   "id": 1,
 // CHECK:STDOUT:   "jsonrpc": "2.0",
 // CHECK:STDOUT:   "result": {
 // CHECK:STDOUT:     "capabilities": {

toolchain/language_server/testdata/notify_parse_error.carbon

@@ -15,6 +15,6 @@
 
 // --- AUTOUPDATE-SPLIT
 
-// CHECK:STDERR: warning: -32602: in call to `textDocument/didOpen`, JSON parse failed: expected object [LanguageServerNotificationParseError]
+// CHECK:STDERR: warning: -32602: in call to `textDocument/didOpen`, JSON parse failed: missing value at (root).textDocument [LanguageServerNotificationParseError]
 // CHECK:STDERR:
 // CHECK:STDOUT:

toolchain/language_server/testdata/unexpected_reply.carbon

@@ -18,6 +18,6 @@
 
 // CHECK:STDERR: warning: unexpected reply to request ID "1": null [LanguageServerUnexpectedReply]
 // CHECK:STDERR:
-// CHECK:STDERR: warning: unexpected reply to request ID "2": 3 [LanguageServerUnexpectedReply]
+// CHECK:STDERR: warning: unexpected reply to request ID "2": {"result":3} [LanguageServerUnexpectedReply]
 // CHECK:STDERR:
 // CHECK:STDOUT:

toolchain/language_server/testdata/unsupported_call.carbon

@@ -10,18 +10,18 @@
 
 
 // --- STDIN
-[[@LSP:unknown-call]]
+[[@LSP-CALL:unknown-call]]
 [[@LSP-NOTIFY:exit]]
 
 // --- AUTOUPDATE-SPLIT
 
-// CHECK:STDOUT: Content-Length: 122{{\r}}
+// CHECK:STDOUT: Content-Length: 120{{\r}}
 // CHECK:STDOUT: {{\r}}
 // CHECK:STDOUT: {
 // CHECK:STDOUT:   "error": {
 // CHECK:STDOUT:     "code": -32601,
 // CHECK:STDOUT:     "message": "unsupported call `unknown-call`"
 // CHECK:STDOUT:   },
-// CHECK:STDOUT:   "id": "1",
+// CHECK:STDOUT:   "id": 1,
 // CHECK:STDOUT:   "jsonrpc": "2.0"
 // CHECK:STDOUT: }