lsp-devtools: Add json and json-compact formatters

This gives more control over how items can be formatted.

docs/lsp-devtools/guide/record-command.rst

@@ -29,6 +29,7 @@ Here are some example usages of the ``record`` command that you may find useful.
 
 The following command will save to a JSON file only the client's info and :class:`pygls:lsprotocol.types.ClientCapabilities` sent during the ``initialize`` request - useful for :ref:`adding clients to pytest-lsp <pytest-lsp-supported-clients>`! 😉
 
+
 ::
 
    lsp-devtools record -f '{{"clientInfo": {.params.clientInfo}, "capabilities": {.params.capabilities}}}' --to-file <client_name>_v<version>.json
@@ -291,21 +292,28 @@ Formatting messages
 Formatters
 ^^^^^^^^^^
 
-``lsp-devtools`` knows how to format the following LSP Types
+``lsp-devtools`` provides the following formatters
+
+``json`` (default)
+  Renders objects as "pretty" JSON, equivalent to ``json.dumps(obj, indent=2)``
 
-``Position``
+``json-compact``
+  Renders objects as JSON with no additional formatting, equivalent to ``json.dumps(obj)``
+
+``position``
    ``{"line": 1, "character": 2}`` will be rendered as ``1:2``
 
-``Range``
+``range``
    ``{"start": {"line": 1, "character": 2}, "end": {"line": 3, "character": 4}}`` will be rendered as ``1:2-3:4``
 
-Additionally, any enum type can be used as a formatter in which case a number will be replaced with the corresponding name, for example::
+
+Additionally, any enum type can be used as a formatter, where numbers will be replaced with their corresponding name, for example::
 
   Format String:
   "{.type|MessageType}"
 
-  Value:    Result:
-  1         Error
-  2         Warning
-  3         Info
-  4         Log
+  Value:          Result:
+  {"type": 1}     Error
+  {"type": 2}     Warning
+  {"type": 3}     Info
+  {"type": 4}     Log

lib/lsp-devtools/changes/130.enhancement.md

@@ -0,0 +1 @@
+Added formatters `json` and `json-compact` that can be used within format strings.

lib/lsp-devtools/lsp_devtools/record/formatters.py

@@ -1,7 +1,9 @@
 import json
 import re
+from functools import partial
 from typing import Any
 from typing import Callable
+from typing import Dict
 from typing import List
 from typing import Optional
 from typing import Tuple
@@ -17,11 +19,11 @@
     cache = lru_cache(None)
 
 
-def format_json(obj: dict) -> str:
+def format_json(obj: dict, *, indent: Union[str, int, None] = 2) -> str:
     if isinstance(obj, str):
         return obj
 
-    return json.dumps(obj, indent=2)
+    return json.dumps(obj, indent=indent)
 
 
 def format_position(position: dict) -> str:
@@ -32,9 +34,11 @@ def format_range(range_: dict) -> str:
     return f"{format_position(range_['start'])}-{format_position(range_['end'])}"
 
 
-FORMATTERS = {
+FORMATTERS: Dict[str, Callable[[Any], str]] = {
     "position": format_position,
     "range": format_range,
+    "json": format_json,
+    "json-compact": partial(format_json, indent=None),
 }
 
 

lib/lsp-devtools/tests/record/test_formatters.py

@@ -18,6 +18,20 @@
             {"method": "textDocument/completion"},
             "The method 'textDocument/completion' was called",
         ),
+        (
+            "{.position|json}",
+            {
+                "position": {"line": 1, "character": 2},
+            },
+            '{\n  "line": 1,\n  "character": 2\n}',
+        ),
+        (
+            "{.position|json-compact}",
+            {
+                "position": {"line": 1, "character": 2},
+            },
+            '{"line": 1, "character": 2}',
+        ),
         (
             "{.method} {.params.textDocument.uri}:{.params.position}",
             {