Add support for the Go language (#1250)

CHANGELOG.md

@@ -9,7 +9,8 @@ Jupytext ChangeLog
 - Some dependencies of the JupyterLab extensions were updated ([#1243](https://github.com/mwouts/jupytext/issues/1243), [#1245](https://github.com/mwouts/jupytext/issues/1245))
 
 **Added**
-- Added support for Lua notebooks ([#1252](https://github.com/mwouts/jupytext/pull/1252)) - thanks to [erentar](https://github.com/erentar) for this contribution
+- Lua notebooks are now supported ([#1252](https://github.com/mwouts/jupytext/pull/1252)) - thanks to [erentar](https://github.com/erentar) for this contribution
+- Go notebooks are supported too ([#1244](https://github.com/mwouts/jupytext/issues/1244))! Many thanks to [Jan Pfeifer](https://github.com/janpfeifer), author of [GoNB](https://github.com/janpfeifer/gonb), and to [HaveF](https://github.com/HaveF) for their help on this topic.
 - Empty prefixes are now allowed in Jupytext format when specified as a dictionary ([#1144](https://github.com/mwouts/jupytext/issues/1144))
 
 

docs/languages.md

@@ -9,6 +9,7 @@ Jupytext works with notebooks in any of the following languages:
 - Coconut
 - F#
 - Gnuplot
+- Go
 - Groovy
 - Haskell
 - IDL

src/jupytext/cell_reader.py

@@ -555,6 +555,11 @@ def uncomment_code_and_magics(self, lines):
                 else:
                     lines = uncomment(lines)
 
+        if self.default_language == "go" and self.language is None:
+            lines = [
+                re.sub(r"^((//\s*)*)(//\s*gonb:%%)", r"\1%%", line) for line in lines
+            ]
+
         if self.cell_type == "code":
             return unescape_code_start(
                 lines, self.ext, self.language or self.default_language

src/jupytext/cell_to_text.py

@@ -135,6 +135,13 @@ def cell_to_text(self):
         if self.cell_type != "code" and not self.metadata and self.use_triple_quotes():
             self.metadata["cell_type"] = self.cell_type
 
+        # Go notebooks have '%%' or '%% -' magic commands that need to be escaped
+        if self.default_language == "go" and self.language == "go":
+            self.source = [
+                re.sub(r"^(//\s*)*(%%\s*$|%%\s+-.*$)", r"\1//gonb:\2", line)
+                for line in self.source
+            ]
+
         if self.is_code():
             return self.code_to_text()
 
@@ -487,6 +494,13 @@ def __init__(self, *args, **kwargs):
 
     def cell_to_text(self):
         """Return the text representation for the cell"""
+        # Go notebooks have '%%' or '%% -' magic commands that need to be escaped
+        if self.default_language == "go" and self.language == "go":
+            self.source = [
+                re.sub(r"^(//\s*)*(%%\s*$|%%\s+-.*$)", r"\1//gonb:\2", line)
+                for line in self.source
+            ]
+
         active = is_active(
             self.ext, self.metadata, same_language(self.language, self.default_language)
         )

src/jupytext/languages.py

@@ -1,4 +1,5 @@
 """Determine notebook or cell language"""
+import re
 
 # Jupyter magic commands that are also languages
 _JUPYTER_LANGUAGES = [
@@ -92,6 +93,7 @@
     },
     ".xsh": {"language": "xonsh", "comment": "#"},
     ".lua": {"language": "lua", "comment": "--"},
+    ".go": {"language": "go", "comment": "//"},
 }
 
 _COMMENT_CHARS = [
@@ -110,6 +112,7 @@
 _JUPYTER_LANGUAGES_LOWER_AND_UPPER = _JUPYTER_LANGUAGES.union(
     {str.upper(lang) for lang in _JUPYTER_LANGUAGES}
 )
+_GO_DOUBLE_PERCENT_COMMAND = re.compile(r"^(%%\s*|%%\s+-.*)$")
 
 
 def default_language_from_metadata_and_ext(metadata, ext, pop_main_language=False):
@@ -206,6 +209,8 @@ def cell_language(source, default_language, custom_cell_magics):
     """Return cell language and language options, if any"""
     if source:
         line = source[0]
+        if default_language == "go" and _GO_DOUBLE_PERCENT_COMMAND.match(line):
+            return None, None
         if default_language == "csharp":
             if line.startswith("#!"):
                 lang = line[2:].strip()

src/jupytext/magics.py

@@ -41,6 +41,10 @@ def get_comment(ext):
 _MAGIC_FORCE_ESC_RE["csharp"] = re.compile(r"^(// |//)*#![a-zA-Z](.*)//\s*escape")
 _MAGIC_FORCE_ESC_RE["csharp"] = re.compile(r"^(// |//)*#![a-zA-Z](.*)//\s*noescape")
 
+# Go magics might start with % or ! or !*
+# (in addition, Go NB might use %% or %% -, see "_GO_DOUBLE_PERCENT_COMMAND")
+_MAGIC_RE["go"] = re.compile(r"^(// |//)*(!|!\*|%|%%|%%%)[a-zA-Z]")
+
 # Commands starting with a question or exclamation mark have to be escaped
 _PYTHON_HELP_OR_BASH_CMD = re.compile(r"^\s*(# |#)*\s*(\?|!)\s*[A-Za-z\.\~\$\\\/\{\}]")
 

tests/data/notebooks/inputs/ipynb_go/hello_world_gonb.ipynb

@@ -0,0 +1,149 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "id": "8795db3a-af9a-4f03-a68d-019330861b54",
+   "metadata": {},
+   "source": [
+    "A notebook that use [GoNB](https://github.com/janpfeifer/gonb)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "50a2fb21-01b3-46d0-9951-f9a1301a85ca",
+   "metadata": {},
+   "source": [
+    "the code below comes from [tutorial.ipynb](https://github.com/janpfeifer/gonb/blob/main/examples/tutorial.ipynb)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "75d8418d-a918-4cc8-b42e-384db01f21ae",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "func main() {\n",
+    "    fmt.Printf(\"Hello World!\")\n",
+    "}"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "3620f46f-efd5-4454-bc29-418297012ce9",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "%%\n",
+    "fmt.Printf(\"Hello World!\")"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "7fed4a43",
+   "metadata": {},
+   "source": [
+    "%% --who=world can pass flags to main func"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "473e2d02",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import (\n",
+    "    \"flag\"\n",
+    "    \"fmt\"\n",
+    ")\n",
+    "\n",
+    "var flagWho = flag.String(\"who\", \"\", \"Your name!\")\n",
+    "\n",
+    "%% --who=world\n",
+    "fmt.Printf(\"Hello %s!\\n\", *flagWho)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "b8e8b4ae",
+   "metadata": {},
+   "source": [
+    "%args also can pass flags"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "348efbe1",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "%args --who=Wally\n",
+    "\n",
+    "func main() {\n",
+    "    flag.Parse()\n",
+    "    fmt.Printf(\"Where is %s?\", *flagWho)\n",
+    "}"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "82f4bb1f-3311-4fca-8025-c54c0305dc64",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import \"github.com/janpfeifer/gonb/gonbui\"\n",
+    "\n",
+    "%%\n",
+    "gonbui.DisplayHtml(`<span style=\"background:pink; color:#111; border-radius: 3px; border: 3px solid orange; font-size: 18px;\">I 🧡 GoNB!</span>`)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "1a5584ff-f346-45cf-95c1-a3e3b7146c6c",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "%%\n",
+    "gonbui.DisplayMarkdown(\"#### Objective\\n\\n1. Have fun coding **Go**;\\n1. Profit...\\n\"+\n",
+    "                       `$$f(x) = \\int_{-\\infty}^{\\infty} e^{-x^2} dx$$`)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "de996381-d92c-4ce6-a135-50cf39288aa1",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "func init_a() {\n",
+    "    fmt.Println(\"init_a\")\n",
+    "}\n",
+    "%%\n",
+    "fmt.Println(\"main\")"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Go (gonb)",
+   "language": "go",
+   "name": "gonb"
+  },
+  "language_info": {
+   "codemirror_mode": "",
+   "file_extension": ".go",
+   "mimetype": "",
+   "name": "go",
+   "nbconvert_exporter": "",
+   "pygments_lexer": "",
+   "version": "go1.21.6"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}

tests/data/notebooks/outputs/ipynb_to_Rmd/hello_world_gonb.Rmd

@@ -0,0 +1,69 @@
+---
+jupyter:
+  kernelspec:
+    display_name: Go (gonb)
+    language: go
+    name: gonb
+---
+
+A notebook that use [GoNB](https://github.com/janpfeifer/gonb)
+
+
+the code below comes from [tutorial.ipynb](https://github.com/janpfeifer/gonb/blob/main/examples/tutorial.ipynb)
+
+```{go}
+func main() {
+    fmt.Printf("Hello World!")
+}
+```
+
+```{go}
+%%
+fmt.Printf("Hello World!")
+```
+
+%% --who=world can pass flags to main func
+
+```{go}
+import (
+    "flag"
+    "fmt"
+)
+
+var flagWho = flag.String("who", "", "Your name!")
+
+%% --who=world
+fmt.Printf("Hello %s!\n", *flagWho)
+```
+
+%args also can pass flags
+
+```{go}
+// %args --who=Wally
+
+func main() {
+    flag.Parse()
+    fmt.Printf("Where is %s?", *flagWho)
+}
+```
+
+```{go}
+import "github.com/janpfeifer/gonb/gonbui"
+
+%%
+gonbui.DisplayHtml(`<span style="background:pink; color:#111; border-radius: 3px; border: 3px solid orange; font-size: 18px;">I 🧡 GoNB!</span>`)
+```
+
+```{go}
+%%
+gonbui.DisplayMarkdown("#### Objective\n\n1. Have fun coding **Go**;\n1. Profit...\n"+
+                       `$$f(x) = \int_{-\infty}^{\infty} e^{-x^2} dx$$`)
+```
+
+```{go}
+func init_a() {
+    fmt.Println("init_a")
+}
+%%
+fmt.Println("main")
+```

tests/data/notebooks/outputs/ipynb_to_hydrogen/hello_world_gonb.go

@@ -0,0 +1,66 @@
+// -*- coding: utf-8 -*-
+// ---
+// jupyter:
+//   kernelspec:
+//     display_name: Go (gonb)
+//     language: go
+//     name: gonb
+// ---
+
+// %% [markdown]
+// A notebook that use [GoNB](https://github.com/janpfeifer/gonb)
+
+// %% [markdown]
+// the code below comes from [tutorial.ipynb](https://github.com/janpfeifer/gonb/blob/main/examples/tutorial.ipynb)
+
+// %%
+func main() {
+    fmt.Printf("Hello World!")
+}
+
+// %%
+//gonb:%%
+fmt.Printf("Hello World!")
+
+// %% [markdown]
+// //gonb:%% --who=world can pass flags to main func
+
+// %%
+import (
+    "flag"
+    "fmt"
+)
+
+var flagWho = flag.String("who", "", "Your name!")
+
+//gonb:%% --who=world
+fmt.Printf("Hello %s!\n", *flagWho)
+
+// %% [markdown]
+// %args also can pass flags
+
+// %%
+%args --who=Wally
+
+func main() {
+    flag.Parse()
+    fmt.Printf("Where is %s?", *flagWho)
+}
+
+// %%
+import "github.com/janpfeifer/gonb/gonbui"
+
+//gonb:%%
+gonbui.DisplayHtml(`<span style="background:pink; color:#111; border-radius: 3px; border: 3px solid orange; font-size: 18px;">I 🧡 GoNB!</span>`)
+
+// %%
+//gonb:%%
+gonbui.DisplayMarkdown("#### Objective\n\n1. Have fun coding **Go**;\n1. Profit...\n"+
+                       `$$f(x) = \int_{-\infty}^{\infty} e^{-x^2} dx$$`)
+
+// %%
+func init_a() {
+    fmt.Println("init_a")
+}
+//gonb:%%
+fmt.Println("main")