Raw string syntax highlighting is misleading

[pwilkin]

Type: Bug

If you use a raw string literal that contains backslashes, the syntax highlighting will be changed to red, but letters after the backslashes and the backslashes themselves will be still marked as yellow, suggesting they are escape characters, i.e.:

dest = r'M:\Updated files'

the "\U" part is colored yellow. As per raw string specification, the only thing that should actually get this treatment is the enclosing quote character when prefixed by a backslash, so in r'foo\'s' the "'" should be recognized as an escape sequence, but otherwise the backspace functions as a normal character (and one of the common uses of raw strings is to provide Windows path literals, so the misleading case will happen often).

Extension version: 2025.1.2025021001
VS Code version: Code 1.97.0 (33fc5a94a3f99ebe7087e8fe79fbe1d37a251016, 2025-02-04T22:41:26.688Z)
OS version: Windows_NT x64 10.0.26100
Modes:

• Python version (& distribution if applicable, e.g. Anaconda): 3.12.6
• Type of virtual environment used (e.g. conda, venv, virtualenv, etc.): System
• Value of the python.languageServer setting: Default

User Settings

languageServer: "Pylance"

Installed Extensions

Extension Name	Extension Id	Version
bun-vscode	ove	0.0.26
continue	Con	0.8.68
debugpy	ms-	2025.0.0
dscodegpt	Dan	3.8.42
githistory	don	0.6.20
intellicode-api-usage-examples	Vis	0.2.9
js-debug	ms-	1.97.0
js-debug-companion	ms-	1.1.3
npm-intellisense	chr	1.4.5
python	ms-	2025.1.2025021001
reflow-markdown	mar	3.1.0
remote-containers	ms-	0.397.0
remote-wsl	ms-	0.88.5
rest-client	hum	0.25.1
ts-debug	kak	0.0.6
vsc-python-indent	Kev	1.19.0
vscode-docker	ms-	1.29.4
vscode-js-profile-table	ms-	1.0.10
vscode-pylance	ms-	2025.2.1
vscode-python-envs	ms-	0.3.10411011
vscodeintellicode	Vis	1.3.2

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-9700K CPU @ 3.60GHz (8 x 3600)
GPU Status	2d_canvas: enabled canvas_oop_rasterization: enabled_on direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: enabled raw_draw: disabled_off_ok skia_graphite: disabled_off video_decode: enabled video_encode: enabled vulkan: disabled_off webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off
Load (avg)	undefined
Memory (System)	23.92GB (10.64GB free)
Process Argv	--crash-reporter-id 24798850-605b-416d-a0f8-7431e116d62e
Screen Reader	no
VM	0%

A/B Experiments

vsliv368:30146709
vspor879:30202332
vspor708:30202333
vspor363:30204092
vscod805:30301674
binariesv615:30325510
vsaa593:30376534
py29gd2263:31024239
c4g48928:30535728
azure-dev_surveyone:30548225
vscrpc:30673769
a9j8j154:30646983
962ge761:30959799
2e7ec940:31000449
pythontbext0:30879054
cppperfnew:31000557
dwnewjupytercf:31046870
nativerepl2:31139839
pythonrstrctxt:31112756
nativeloc2:31192216
iacca1:31171482
5fd0e150:31155592
dwcopilot:31170013
stablechunks:31184530
6074i472:31201624
dwoutputs:31233690
9064b325:31222308
copilot_t_ci:31222730
jda6j935:31233686

[debonte]

This is a dupe of #6114. Specifically, see this comment: #6114 (comment)