fix hanging on vfmt-ing large files on windows (#130)

src/server/features_formatting.v

@@ -3,6 +3,7 @@ module server
 import lsp
 import os
 import server.tform
+import loglib
 
 const temp_formatting_file_path = os.join_path(os.temp_dir(), 'v-analyzer-formatting-temp.v')
 
@@ -14,23 +15,36 @@ pub fn (mut ls LanguageServer) formatting(params lsp.DocumentFormattingParams) !
 		return error('Cannot write temp file for formatting: ${err}')
 	}
 
-	mut fmt_proc := ls.launch_tool('fmt', temp_formatting_file_path)!
+	loglib.with_fields({
+		'uri': file.uri.str()
+	}).info('Formatting file')
+
+	mut fmt_proc := ls.launch_tool('fmt', os.norm_path(temp_formatting_file_path))!
 	defer {
 		fmt_proc.close()
 	}
+	fmt_proc.run()
+
+	// read entire output until EOF
+	mut output := fmt_proc.stdout_slurp()
 	fmt_proc.wait()
 
-	if fmt_proc.code != 0 {
-		errors := fmt_proc.stderr_slurp().trim_space()
-		ls.client.show_message(errors, .info)
-		return error('Formatting failed: ${errors}')
-	}
+	loglib.with_fields({
+		'code':   fmt_proc.code.str()
+		'status': fmt_proc.status.str()
+	}).info('Formatting finished')
 
-	mut output := fmt_proc.stdout_slurp()
 	$if windows {
 		output = output.replace('\r\r', '\r')
 	}
 
+	if fmt_proc.code != 0 && fmt_proc.status == .exited {
+		errors := fmt_proc.stderr_slurp().trim_space()
+		ls.client.show_message(errors, .info)
+		return error('Formatting failed: ${errors}')
+		// return []
+	}
+
 	return [
 		lsp.TextEdit{
 			range:    tform.text_range_to_lsp_range(file.psi_file.root().text_range())

src/server/features_formatting_test.v

@@ -0,0 +1,35 @@
+module server
+
+import lsp
+import os
+import analyzer
+import analyzer.psi
+import analyzer.parser
+
+fn test_large_file() {
+	test_file := os.real_path(@VMODROOT + '/src/server/general.v')
+
+	src := os.read_file(test_file) or { panic('Cannot read file') }
+
+	mut ls := LanguageServer.new(analyzer.IndexingManager.new())
+	ls.setup_toolchain()
+	ls.setup_vpaths()
+
+	uri := lsp.document_uri_from_path(test_file)
+	res := parser.parse_code(src)
+	psi_file := psi.new_psi_file(uri.path(), res.tree, res.source_text)
+	ls.opened_files[uri] = analyzer.OpenedFile{
+		uri:      uri
+		version:  0
+		psi_file: psi_file
+	}
+
+	params := lsp.DocumentFormattingParams{
+		text_document: lsp.TextDocumentIdentifier{
+			uri: uri
+		}
+	}
+
+	text_edit_result := ls.formatting(params) or { panic('Cannot format file') }
+	assert text_edit_result.len == 1
+}