Unify handling of multi-line input between cadabra2-gtk and cadabra2-cli by using the CdbPython.cc code also for the latter. Cleanup.

Author: Kasper Peeters

core/cadabra2-cli.cc

@@ -53,6 +53,7 @@ Shell::Shell(Flags flags)
 	colour_info    = no_colour ? "" : "\033[36m";
 	colour_success = no_colour ? "" : "\033[32m";
 	colour_reset   = no_colour ? "" : "\033[0m";
+	colour_bold    = no_colour ? "" : "\033[1m";
 
 	if (!(flags & Flags::NoReadline)) {
 		set_histfile();
@@ -94,8 +95,9 @@ void Shell::interact()
 
 	// Print startup info banner
 	if (!(flags & Flags::NoBanner)) {
-		write_stdout("Cadabra " CADABRA_VERSION_FULL " (build " CADABRA_VERSION_BUILD
-						 " dated " CADABRA_VERSION_DATE ")");
+		write_stdout(colour_bold + std::string("Cadabra ") + std::string(CADABRA_VERSION_FULL) + colour_reset
+						 + " (build " + std::string(CADABRA_VERSION_BUILD) +
+						 " dated " + std::string(CADABRA_VERSION_DATE) + ")");
 		write_stdout("Copyright (C) " COPYRIGHT_YEARS "  Kasper Peeters <[email protected]>");
 		write_stdout("Info at https://cadabra.science/");
 		write_stdout("Available under the terms of the GNU GPL v3.");
@@ -126,7 +128,10 @@ void Shell::interact()
 		using namespace std::placeholders;
 		if (!(flags & Flags::NoReadline))
 			SetCompletionCallback(std::bind(&Shell::set_completion_callback, this, _1, _2));
+
+		
 		if (collect.empty()) {
+			curline.clear();
 			if (get_input(get_ps1(), curline)) {
 				PyErr_SetNone(PyExc_KeyboardInterrupt);
 				handle_error();
@@ -371,66 +376,53 @@ void Shell::process_ps1(const std::string& line)
 	{
 	// Convert cadabra to python
 	bool display = !(flags & Flags::IgnoreSemicolons);
+
+	// In contrast to notebook cell processing, what we do here is
+	// simpler. We just convert this first line. If it is complete
+	// python code, we can execute it. If not, we just take this
+	// line together with future lines until an empty line is
+	// input, and then we convert & execute the whole block.
+	// So we don't really do anything with ConvertData nor with
+	// the result of `convert_line`.
 	cadabra::ConvertData cv;
 	std::pair<std::string, std::string> res = cadabra::convert_line(line, cv, display);
-	// FIXME: we need to process res.first
 	const std::string& output = res.second;
 	if (output == "::empty") {
-		// Cadabra continuation line, add to collect
-		collect += line + "\n";
+		// Cadabra continuation line, add the unprocessed line to collect
+		collect = line + "\n";
 		return;
 		}
 
-	try {
-		py::object res = evaluate(output);
-		if (!res.is_none()) {
-			write_stdout(str(res));
-			globals["_"] = res;
-			}
-		}
-	catch (py::error_already_set& eval_err) {
-		if (eval_err.matches(PyExc_SyntaxError)) {
-			// Might have valid Python, but needs to be executed not evaluated.
-			try {
-				execute(output);
-				}
-			catch (py::error_already_set& exec_err) {
-				bool need_more = false;
-				// Check if we need more input. The approach taken is from the Python codeop library:
-				// https://github.com/python/cpython/blob/8c93a63c03ddc789040a6ad50a18af1df7764884/Lib/codeop.py#L19
-				// First compile with a newline appended. If it compiles, then we need more input.
-				std::string output_with_nl = output + "\n";
-				auto co_with_nl = py::reinterpret_steal<py::object>(
-					Py_CompileString(output_with_nl.c_str(), "<internal>", Py_file_input));
-				if (co_with_nl) {
-					need_more = true;
-					}
-				else {
-					// Recompile with two newlines appended. Compare the error generated by the two compilations:
-					// if they are different then we need more, otherwise it is a genuine error
-					py::error_already_set err1; // Save&clear error from co_with_nl
-					std::string output_with_nlnl = output + "\n\n";
-					auto co_with_nlnl = py::reinterpret_steal<py::object>(
-						Py_CompileString(output_with_nlnl.c_str(), "<internal>", Py_file_input));
-					py::error_already_set err2; // Save&clear error from co_with_nlnl
-					need_more = (repr(err1.type()) != repr(err2.type()) || repr(err1.value()) != repr(err2.value()));
-					}
-
-				if (need_more)
-					collect += "\n";
-				else
-					handle_error(exec_err);
+	std::string error;
+	int status = cadabra::is_python_code_complete(output, error);
+	switch(status) {
+		case 0:
+			// std::cerr << "seting collect to\n|" << res.first + res.second << "|" << std::endl;
+			collect = res.first + res.second + "\n";
+			break;
+		case 1: {
+			std::string tmp = res.first + res.second;
+			collect.clear();
+			if(tmp.size()>0) {
+				// std::cerr << "executing ps1\n|" << tmp << "|" << std::endl;
+				execute(tmp);
 				}
+			break;
 			}
-		else {
-			handle_error(eval_err);
-			}
+		case -1:
+			collect.clear();
+			throw ParseException(error);
+		case -2:
+			collect.clear();
+			throw ParseException(error);
+		default:
+			throw InternalError("Code completion check returned invalid response.");
 		}
 	}
 
 void Shell::process_ps2(const std::string& line)
 	{
-	if (!line.empty()) {
+	if(!line.empty()) {
 		collect += line + "\n";
 		return;
 		}
@@ -439,6 +431,7 @@ void Shell::process_ps2(const std::string& line)
 	std::string error;
 	std::string code = cadabra::cdb2python_string(collect, display, error);
 	collect.clear();
+	// std::cerr << "executing ps2\n|" << code << "|" << std::endl;
 	execute(code);
 	}
 
@@ -480,6 +473,7 @@ std::string Shell::get_ps2()
 
 void Shell::handle_error()
 	{
+	collect.clear();
 	if (PyErr_Occurred()) {
 		py::error_already_set err;
 		handle_error(err);

core/cadabra2-cli.hh

@@ -70,6 +70,7 @@ class Shell : public pybind11::scoped_interpreter {
 		const char* colour_info;
 		const char* colour_success;
 		const char* colour_reset;
+		const char* colour_bold;
 		Flags flags;
 };