src/formatitko/formatitko.py

@@ -14,7 +14,7 @@ from .katex import KatexClient
 from .html import html
 from .tex import tex
 from .images import ImageProcessor
-from .output_generator import OutputGenerator
+from .output_generator import OutputGenerator, FormatitkoRecursiveError
 from .html_generator import HTMLGenerator
 from .transform_processor import TransformProcessor
 from .pandoc_processor import PandocProcessor
@@ -54,9 +54,15 @@ def main():
 	doc = import_md(open(args.input_filename, "r").read())
 
 	if args.debug:
-		OutputGenerator(sys.stdout).generate(doc)
+		try:
+			OutputGenerator(sys.stdout).generate(doc)
+		except FormatitkoRecursiveError as e:
+			e.pretty_print()
 
-	doc = TransformProcessor(args.input_filename).transform(doc)
+	try:
+		doc = TransformProcessor(args.input_filename).transform(doc)
+	except FormatitkoRecursiveError as e:
+		e.pretty_print()
 
 	# Initialize the image processor (this just keeps some basic state)
 	imageProcessor = ImageProcessor(args.img_public_dir, args.img_web_path, args.img_cache_dir, *args.img_lookup_dirs)
@@ -65,11 +71,18 @@ def main():
 		# Initialize KaTeX client (this runs the node app and connects to a unix socket)
 		with KatexClient(socket=args.katex_socket) as katexClient:
 			with open(args.output_html, "w") as file:
-				HTMLGenerator(file, katexClient, imageProcessor).generate(doc)
+				try:
+					HTMLGenerator(file, katexClient, imageProcessor).generate(doc)
+				except FormatitkoRecursiveError as e:
+					e.pretty_print()
 
 	if args.output_tex is not None:
 		with open(args.output_tex, "w") as file:
-			UCWTexGenerator(file, imageProcessor).generate(doc)
+			try:
+				UCWTexGenerator(file, imageProcessor).generate(doc)
+			except FormatitkoRecursiveError as e:
+				e.pretty_print()
+
 
 	if args.output_md is not None:
 		with open(args.output_md, "w") as file:
@@ -83,7 +96,10 @@ def main():
 		if args.output_tex is None:
 			fd = tempfile.NamedTemporaryFile(dir=".", suffix=".tex")
 			with open(fd.name, "w") as file:
-				UCWTexGenerator(file, imageProcessor).generate(doc)
+				try:
+					UCWTexGenerator(file, imageProcessor).generate(doc)
+				except FormatitkoRecursiveError as e:
+					e.pretty_print()
 			filename = fd.name
 		else:
 			filename = args.output_tex
@@ -93,7 +109,10 @@ def main():
 
 	if args.debug:
 		print("-----------------------------------")
-		OutputGenerator(sys.stdout).generate(doc)
+		try:
+			OutputGenerator(sys.stdout).generate(doc)
+		except FormatitkoRecursiveError as e:
+			e.pretty_print()
 
 
 if __name__ == "__main__":

src/formatitko/katex.py

@@ -79,7 +79,7 @@ class KatexClient:
 		if "error" in response:
 			raise KatexServerError(response["error"])
 		if "error" in response["results"][0]:
-			raise KatexError(response["results"][0]["error"])
+			raise KatexError(response["results"][0]["error"] + " in $" + tex + "$")
 		else:
 			return response["results"][0]["html"]
 

src/formatitko/nop_processor.py

@@ -7,15 +7,20 @@ from typing import Union, Callable
 
 from .whitespace import NBSP
 from .elements import FQuoted
-from .context import Group, InlineGroup, BlockGroup
+from .context import Group, InlineGroup, BlockGroup, Context
 from .whitespace import Whitespace
 from .command import BlockCommand, InlineCommand, CodeCommand, Command
+from .output_generator import FormatitkoRecursiveError
 
 ELCl = Union[Element, ListContainer, list[Union[Element, ListContainer]]]
 
+class DoubleDocError(Exception):
+	"TransformProcessor should only ever see a single Doc."
+	pass
 
 class NOPProcessor:
 	TYPE_DICT: dict[type, Callable]
+	context: Union[Context, None] = None
 
 	class UnknownElementError(Exception):
 		f"An unknown Element has been passed to the NOPProcessor, probably because panflute introduced a new one."
@@ -96,23 +101,30 @@ class NOPProcessor:
 		return []
 
 	def transform(self, e: ELCl) -> ELCl:
-		if isinstance(e, list):
-			return self.transform_list(e)
-		elif isinstance(e, ListContainer):
-			return self.transform_ListContainer(e)
-
-		for transformer in self.get_pretransformers():
-			e = transformer(e)
-
 		try:
-			e = self.TYPE_DICT[type(e)](e)
-		except KeyError:
-			raise self.UnknownElementError(type(e))
-
-		for transformer in self.get_posttransformers():
-			e = transformer(e)
-
-		return e
+			if isinstance(e, list):
+				return self.transform_list(e)
+			elif isinstance(e, ListContainer):
+				return self.transform_ListContainer(e)
+
+			for transformer in self.get_pretransformers():
+				e = transformer(e)
+
+			try:
+				e = self.TYPE_DICT[type(e)](e)
+			except KeyError:
+				raise self.UnknownElementError(type(e))
+
+			for transformer in self.get_posttransformers():
+				e = transformer(e)
+
+			return e
+		except FormatitkoRecursiveError as err:
+			if not isinstance(e, ListContainer):
+				err.add_element(e)
+			raise err
+		except Exception as err:
+			raise FormatitkoRecursiveError(e, self.context) from err
 
 	def transform_list(self, e: list[Union[Element, ListContainer]]) -> list[Union[Element, ListContainer]]:
 		for i in range(len(e)):
@@ -293,6 +305,9 @@ class NOPProcessor:
 		return e
 
 	def transform_Doc(self, e: Doc) -> Doc:
+		if self.context is not None:
+			raise DoubleDocError()
+		self.context = Context(e, self.root_file_path)
 		e.content = self.transform(e.content)
 		return e
 

src/formatitko/output_generator.py

@@ -3,18 +3,56 @@ from panflute import Cite, Code, Emph, Image, LineBreak, Link, Math, Note, Quote
 from panflute import BlockQuote, BulletList, Citation, CodeBlock, Definition, DefinitionItem, DefinitionList, Div, Figure, Header, HorizontalRule, LineBlock, LineItem, ListItem, MetaBlocks, MetaBool, MetaInlines, MetaList, MetaMap, MetaString, Null, OrderedList, Para, Plain, RawBlock, Table, TableBody, TableFoot, TableHead
 from panflute import TableRow, TableCell, Caption, Doc
 from panflute import MetaValue
+from panflute import stringify
 from typing import Union, Callable
 
 from .whitespace import NBSP
 from .elements import FQuoted
 from .context import Group, InlineGroup, BlockGroup, Context
 
-import re
+
+import sys
 
 class UnknownElementError(Exception):
 	"An unknown Element has been passed to the OutputGenerator, probably because panflute introduced a new one."
 	pass
 
+
+class FormatitkoRecursiveError(Exception):
+	"A generic exception which wraps other exceptions and adds element-based traceback"
+	elements: list[Union[Element, ListContainer, list[Union[Element, ListContainer]]]]
+	context: Context
+
+	def __init__(self, e: Union[Element, ListContainer, list[Union[Element, ListContainer]]], context: Context, *args):
+		self.elements = [e]
+		self.context = context
+		super().__init__(args)
+
+	def add_element(self, e: Union[Element, ListContainer, list[Union[Element, ListContainer]]]):
+		self.elements.append(e)
+
+	def pretty_print(self):
+		def eprint(*args, **kwargs):
+			print(*args, file=sys.stderr, **kwargs)
+
+		def print_filename_recursive(context: Context):
+			return context.filename +\
+				((" (included from " + print_filename_recursive(context.parent) + ")") if context.parent else "")
+		eprint(f"Error occured in file {print_filename_recursive(self.context)} in ", end="")
+		line = None
+		for i in range(len(self.elements)-1, 0, -1):
+			if hasattr(self.elements[i], "content") and len(self.elements[i].content) > 0 and isinstance(self.elements[i].content[0], Inline) and line is None:
+				line = self.elements[i]
+			eprint(type(self.elements[i]).__name__ + "[" + (str(self.elements[i-1].index) if isinstance(self.elements[i-1].index, int) else "") + "]", end=": ")
+		if line:
+			eprint()
+			eprint('on line: "' + stringify(line).strip() + '"', end="")
+		eprint()
+		eprint("in element: " + str(self.elements[0]).replace("\n", "\\n"))
+		sys.tracebacklimit = 0
+		raise self.__cause__ from None
+
+
 class OutputGenerator:
 	_empty_lines: int
 	context: Union[Context, None]
@@ -101,28 +139,35 @@ class OutputGenerator:
 		}
 
 	def generate(self, e: Union[Element, ListContainer, list[Union[Element, ListContainer]]]):
-		if isinstance(e, Group):
-			old_context = self.context
-			self.context = e.context
-		if isinstance(e, list):
-			self.generate_list(e)
-		elif isinstance(e, ListContainer):
-			self.generate_ListContainer(e)
-		elif isinstance(e, Inline):
-			self.generate_Inline(e)
-		elif isinstance(e, Block):
-			self.generate_Block(e)
-		elif isinstance(e, MetaValue):
-			self.generate_MetaValue(e)
-		elif isinstance(e, MetaList):
-			self.generate_MetaList(e)
-		else:
-			try:
-				self.TYPE_DICT_MISC[type(e)](e)
-			except KeyError:
-				raise UnknownElementError(type(e))
-		if isinstance(e, Group):
-			self.context = old_context
+		try:
+			if isinstance(e, Group):
+				old_context = self.context
+				self.context = e.context
+			if isinstance(e, list):
+				self.generate_list(e)
+			elif isinstance(e, ListContainer):
+				self.generate_ListContainer(e)
+			elif isinstance(e, Inline):
+				self.generate_Inline(e)
+			elif isinstance(e, Block):
+				self.generate_Block(e)
+			elif isinstance(e, MetaValue):
+				self.generate_MetaValue(e)
+			elif isinstance(e, MetaList):
+				self.generate_MetaList(e)
+			else:
+				try:
+					self.TYPE_DICT_MISC[type(e)](e)
+				except KeyError as err:
+					raise UnknownElementError(type(e)) from err
+			if isinstance(e, Group):
+				self.context = old_context
+		except FormatitkoRecursiveError as err:
+			if not isinstance(e, ListContainer):
+				err.add_element(e)
+			raise err
+		except Exception as err:
+			raise FormatitkoRecursiveError(e, self.context) from err
 
 	def escape_special_chars(self, text: str) -> str:
 		return text

src/formatitko/transform_processor.py

@@ -20,15 +20,10 @@ from .context import Context, CommandCallable
 from .whitespace import Whitespace, bavlna
 from .command import BlockCommand, InlineCommand, CodeCommand, Command
 from .command_util import handle_command_define, parse_command
-from .nop_processor import NOPProcessor, ELCl
-
-class DoubleDocError(Exception):
-	"TransformProcessor should only ever see a single Doc."
-	pass
+from .nop_processor import NOPProcessor, ELCl, DoubleDocError
 
 class TransformProcessor(NOPProcessor):
 	
-	context: Union[Context, None] = None
 	root_file_path: str
 	root_highlight_style: str = "default"
 	_command_modules: list[tuple[Union[dict[str, CommandCallable], ModuleType], str]] = []

test/test-files/test-partial.md

@@ -56,6 +56,15 @@ $$
 $$
 
 
+<!--There is an inline *emphasis with $math \error$*.-->
+
+<!--
+```python {.run}
+print("bruh")
+raise Exception("Jsem piča")
+```
+-->
+
 ![This is a figure, go figure...](logo.svg){width=25%}What
 
 ![This is a figure, go figure...](logo.pdf){width=50%}