Commit Graph

3892 Commits

Author SHA1 Message Date
Damien George
18acd0318f py/gc: Update debug code to compile with changes to qstr pool types.
Following on from 18b1ba086c and
f46a7140f5.

Signed-off-by: Damien George <damien@micropython.org>
2022-02-17 11:17:21 +11:00
Artyom Skrobov
f46a7140f5 py/qstr: Use const consistently to avoid a cast.
Originally at adafruit#4707

Signed-off-by: Artyom Skrobov <tyomitch@gmail.com>
2022-02-11 22:55:02 +11:00
Artyom Skrobov
18b1ba086c py/qstr: Separate hash and len from string data.
This allows the compiler to merge strings: e.g. "update",
"difference_update" and "symmetric_difference_update" will all point to the
same memory.

No functional change.

The size reduction depends on the number of qstrs in the build.  The change
this commit brings is:

   bare-arm:    -4 -0.007%
minimal x86:  +150 +0.092% [incl +48(data)]
   unix x64:  -608 -0.118%
unix nanbox:  -572 -0.126% [incl +32(data)]
      stm32: -1392 -0.352% PYBV10
     cc3200:  -448 -0.244%
    esp8266: -1208 -0.173% GENERIC
      esp32: -1028 -0.068% GENERIC[incl -1020(data)]
        nrf:  -440 -0.252% pca10040
        rp2: -1072 -0.217% PICO
       samd:  -368 -0.264% ADAFRUIT_ITSYBITSY_M4_EXPRESS

Performance is also improved (on bare metal at least) for the
core_import_mpy_multi.py, core_import_mpy_single.py and core_qstr.py
performance benchmarks.

Originally at adafruit#4583

Signed-off-by: Artyom Skrobov <tyomitch@gmail.com>
2022-02-11 22:52:32 +11:00
Damien George
fbd47fc46c ports: Consolidate inclusion of umachine module in built-ins.
The inclusion of `umachine` in the list of built-in modules is now done
centrally in py/objmodule.c.  Enabling MICROPY_PY_MACHINE will include this
module.

As part of this, all ports now have `umachine` as the core module name
(previously some had only `machine` as the name).

Signed-off-by: Damien George <damien@micropython.org>
2022-02-03 10:08:54 +11:00
stijn
dd6967202a py/modmath: Add math.tau, math.nan and math.inf constants.
Configurable by the new MICROPY_PY_MATH_CONSTANTS option.
2022-01-23 09:28:33 +11:00
stijn
a9448c0a86 all: Fix MICROPY_OBJ_REPR_D compilation with msvc. 2022-01-23 09:25:01 +11:00
Jeff Epler
037b2c72a1 py/objstr: Support '{:08}'.format("Jan") like Python 3.10.
The new test has an .exp file, because it is not compatible with Python 3.9
and lower.

See CPython version of the issue at https://bugs.python.org/issue27772

Signed-off-by: Jeff Epler <jepler@gmail.com>
2022-01-19 15:34:32 +11:00
Damien George
da4b38e756 all: Bump version to 1.18.
Signed-off-by: Damien George <damien@micropython.org>
2022-01-17 09:50:31 +11:00
Damien George
772058a6bd py/mpconfig.h: Define MICROPY_PY_USSL_FINALISER only if not defined.
So a port can define it even if MICROPY_PY_USSL is not defined.

Signed-off-by: Damien George <damien@micropython.org>
2022-01-07 23:59:17 +11:00
stijn
22cf0940e1 py/modbuiltins: Add additional macro for extending builtins.
Mainly useful for defining additional globals in boards and variants.
2022-01-07 11:36:52 +11:00
Emilie Feral
58b56b91c4 py/qstr: Reset mpstate.qstr_last_chunk before raising an error.
The qstr_last_chunk is not collected by the garbage collector.  This relies
on the assertion that qstr_pool_t also references the qstr_last_chunk.  If
an exception is raised while allocating the qstr_pool_t, qstr_last_chunk
has to be invalidated not to become a dangling reference at the next
garbage collection.

Signed-off-by: Emilie Feral <emilie.feral@numworks.com>
2022-01-06 13:00:43 +11:00
Damien George
aac5a97d08 ports: Move '.frozen' to second entry in sys.path.
In commit 86ce442607 the '.frozen' entry was
added at the start of sys.path, to allow control over when frozen modules
are searched during import, and retain existing behaviour whereby frozen
was searched before the filesystem.

But Python semantics of sys.path require sys.path[0] to be the directory of
the currently executing script, or ''.

This commit moves the '.frozen' entry to second place in sys.path, so
sys.path[0] retains its correct value (described above).

Signed-off-by: Damien George <damien@micropython.org>
2021-12-29 23:55:36 +11:00
Damien George
2c139bbf4e py/mpz: Fix bugs with bitwise of -0 by ensuring all 0's are positive.
This commit makes sure that the value zero is always encoded in an mpz_t as
neg=0 and len=0 (previously it was just len=0).

This invariant is needed for some of the bitwise operations that operate on
negative numbers, because they cannot handle -0.  For example
(-((1<<100)-(1<<100)))|1 was being computed as -65535, instead of 1.

Fixes issue #8042.

Signed-off-by: Damien George <damien@micropython.org>
2021-12-21 18:00:05 +11:00
Damien George
fe9ffff9c0 py/mpstate.h: Only include sys.path/argv objects in state when enabled.
The mp_sys_path_obj and mp_sys_argv_obj objects are only used by the
runtime and accessible from Python if MICROPY_PY_SYS is enabled.  So
exclude them from the runtime state if this option is disabled.

Signed-off-by: Damien George <damien@micropython.org>
2021-12-19 08:55:40 +11:00
Damien George
de43b500bd py/runtime: Allow initialising sys.path/argv with defaults.
If MICROPY_PY_SYS_PATH_ARGV_DEFAULTS is enabled (which it is by default)
then sys.path and sys.argv will be initialised and populated with default
values.  This keeps all bare-metal ports aligned.

Signed-off-by: Damien George <damien@micropython.org>
2021-12-18 00:08:07 +11:00
Jim Mussared
d6d4a5819b py/mkrules.cmake: Set frozen preprocessor defs early.
This ensures MICROPY_QSTR_EXTRA_POOL and MICROPY_MODULE_FROZEN_MPY are set
if necessary before the CFLAGS are extracted for QSTR generation.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2021-12-18 00:05:18 +11:00
Jim Mussared
e0bf4611c3 py: Only search frozen modules when '.frozen' is found in sys.path.
This changes makemanifest.py & mpy-tool.py to merge string and mpy names
into the same list (now mp_frozen_names).

The various paths for loading a frozen module (mp_find_frozen_module) and
checking existence of a frozen module (mp_frozen_stat) use a common
function that searches this list.

In addition, the frozen lookup will now only take place if the path starts
with ".frozen", which needs to be added to sys.path.

This fixes issues #1804, #2322, #3509, #6419.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2021-12-18 00:01:59 +11:00
Jim Mussared
92353c2911 all: Remove support for FROZEN_DIR and FROZEN_MPY_DIR.
These have been deprecated for over two years in favour of FROZEN_MANIFEST
and manifest.py.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2021-12-17 23:54:05 +11:00
Jim Mussared
cc23e99f32 py/modio: Remove io.resource_stream function.
This feature is not enabled on any port, it's not in CPython's io module,
and functionality is better suited to the micropython-lib implementation of
pkg_resources.
2021-12-17 23:53:44 +11:00
Damien George
d6dc4cb65a py/showbc: Fix printing of raw bytecode header on nanbox builds.
Signed-off-by: Damien George <damien@micropython.org>
2021-12-15 16:54:47 +11:00
Jim Mussared
a7fa18c203 py/builtinimport: Refactor module importing.
Simplify and document/comment the handling of builtin import for:
- already-loaded modules
- built-in modules
- built-in umodules (formerly weak links)
- filesystem modules

Retains existing functionality with smaller code size but should also
facilitate potential new features (built-in packages, controlling the
frozen path).

Also makes the (unix-only) -m behavior a bit more obvious and configurable.

Code size change with this commit:

   bare-arm:    +0 +0.000%
minimal x86:   -64 -0.039%
   unix x64:   -32 -0.006%
unix nanbox:    -4 -0.001%
      stm32:  -184 -0.047% PYBV10
     cc3200:  -120 -0.065%
    esp8266:  -228 -0.033% GENERIC
      esp32:  -268 -0.018% GENERIC[incl +16(data)]
        nrf:  -152 -0.087% pca10040
        rp2:  -256 -0.052% PICO
       samd:   -80 -0.057% ADAFRUIT_ITSYBITSY_M4_EXPRESS
2021-12-01 13:23:34 +11:00
Damien George
a0890983ea py/objfun.h: Remove obsolete comments about entries in extra_args.
These two entries were removed in 049a7a8153

Signed-off-by: Damien George <damien@micropython.org>
2021-11-25 23:24:40 +11:00
Damien George
11ed94797d py/lexer: Support nested [] and {} characters within f-string params.
Signed-off-by: Damien George <damien@micropython.org>
2021-11-25 21:50:58 +11:00
Laurens Valk
e2ca8ab8fc py/runtime: Allow types to use both .attr and .locals_dict.
Make it possible to proceed to a regular lookup in locals_dict if the
custom type->attr fails.  This allows type->attr to extend rather than
completely replace the lookup in locals_dict.

This is useful for custom builtin classes that have mostly regular methods
but just a few special attributes/properties.  This way, type->attr needs
to deal with the special cases only and the default lookup will be used for
generic methods.

Signed-off-by: Laurens Valk <laurens@pybricks.com>
2021-11-22 12:10:35 +11:00
Damien George
123dcdb8e5 py/modsys: Replace non-ASCII quote char with ASCII char.
The source code should stay 7-bit ASCII clean.

Signed-off-by: Damien George <damien@micropython.org>
2021-11-19 17:26:04 +11:00
Damien George
78ab2eeda3 py/showbc: Print unary-op string when dumping bytecode.
Signed-off-by: Damien George <damien@micropython.org>
2021-11-19 17:05:40 +11:00
Laurens Valk
fe120484b6 py/gc: Add hook to run code during time consuming GC operations.
This makes it possible for cooperative multitasking systems to keep running
event loops during garbage collector operations.

For example, this can be used to ensure that a motor control loop runs
approximately each 5 ms.  Without this hook, the loop time can jump to
about 15 ms.

Addresses #3475.

Signed-off-by: Laurens Valk <laurens@pybricks.com>
2021-11-01 15:39:37 +11:00
Damien George
c62351fbd6 py/mpconfig.h: Revert MICROPY_REPL_INFO to disabled at all levels.
This is an stm32-specific feature that's accessed via the pyb module, so
not something that will be widely enabled.

Signed-off-by: Damien George <damien@micropython.org>
2021-11-01 15:18:22 +11:00
Jim Mussared
0e236eef08 py/mpconfig.h: Define the "extra" feature level.
Some of these will later be moved to CORE or BASIC, but EXTRA is a good
starting point based on what stm32 uses.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2021-11-01 14:57:28 +11:00
Mike Wadsten
fe2bc92b4d py/runtime: Fix crash when exc __new__ doesn't return an exc instance.
See CPython bug https://bugs.python.org/issue39091 for more details.
2021-10-21 12:32:16 +11:00
Damien George
8412568e7b py: Add wrapper macros so hot VM functions can go in fast code location.
For example, on esp32 they can go in iRAM to improve performance.

Signed-off-by: Damien George <damien@micropython.org>
2021-10-15 23:31:19 +11:00
stijn
ea880d5674 py/builtinimport: Forward all debug printing to MICROPY_DEBUG_PRINTER. 2021-09-24 13:17:19 +10:00
iabdalkader
2c5e9bbdfa extmod: Add platform module.
It contains the compiler version, and underlying system HAL/SDK version.
2021-09-19 23:35:10 +10:00
Jim Mussared
b326edf68c all: Remove MICROPY_OPT_CACHE_MAP_LOOKUP_IN_BYTECODE.
This commit removes all parts of code associated with the existing
MICROPY_OPT_CACHE_MAP_LOOKUP_IN_BYTECODE optimisation option, including the
-mcache-lookup-bc option to mpy-cross.

This feature originally provided a significant performance boost for Unix,
but wasn't able to be enabled for MCU targets (due to frozen bytecode), and
added significant extra complexity to generating and distributing .mpy
files.

The equivalent performance gain is now provided by the combination of
MICROPY_OPT_LOAD_ATTR_FAST_PATH and MICROPY_OPT_MAP_LOOKUP_CACHE (which has
been enabled on the unix port in the previous commit).

It's hard to provide precise performance numbers, but tests have been run
on a wide variety of architectures (x86-64, ARM Cortex, Aarch64, RISC-V,
xtensa) and they all generally agree on the qualitative improvements seen
by the combination of MICROPY_OPT_LOAD_ATTR_FAST_PATH and
MICROPY_OPT_MAP_LOOKUP_CACHE.

For example, on a "quiet" Linux x64 environment (i3-5010U @ 2.10GHz) the
change from CACHE_MAP_LOOKUP_IN_BYTECODE, to LOAD_ATTR_FAST_PATH combined
with MAP_LOOKUP_CACHE is:

diff of scores (higher is better)
N=2000 M=2000       bccache -> attrmapcache      diff      diff% (error%)
bm_chaos.py        13742.56 ->   13905.67 :   +163.11 =  +1.187% (+/-3.75%)
bm_fannkuch.py        60.13 ->      61.34 :     +1.21 =  +2.012% (+/-2.11%)
bm_fft.py         113083.20 ->  114793.68 :  +1710.48 =  +1.513% (+/-1.57%)
bm_float.py       256552.80 ->  243908.29 : -12644.51 =  -4.929% (+/-1.90%)
bm_hexiom.py         521.93 ->     625.41 :   +103.48 = +19.826% (+/-0.40%)
bm_nqueens.py     197544.25 ->  217713.12 : +20168.87 = +10.210% (+/-3.01%)
bm_pidigits.py      8072.98 ->    8198.75 :   +125.77 =  +1.558% (+/-3.22%)
misc_aes.py        17283.45 ->   16480.52 :   -802.93 =  -4.646% (+/-0.82%)
misc_mandel.py     99083.99 ->  128939.84 : +29855.85 = +30.132% (+/-5.88%)
misc_pystone.py    83860.10 ->   82592.56 :  -1267.54 =  -1.511% (+/-2.27%)
misc_raytrace.py   21490.40 ->   22227.23 :   +736.83 =  +3.429% (+/-1.88%)

This shows that the new optimisations are at least as good as the existing
inline-bytecode-caching, and are sometimes much better (because the new
ones apply caching to a wider variety of map lookups).

The new optimisations can also benefit code generated by the native
emitter, because they apply to the runtime rather than the generated code.
The improvement for the native emitter when LOAD_ATTR_FAST_PATH and
MAP_LOOKUP_CACHE are enabled is (same Linux environment as above):

diff of scores (higher is better)
N=2000 M=2000        native -> nat-attrmapcache  diff      diff% (error%)
bm_chaos.py        14130.62 ->   15464.68 :  +1334.06 =  +9.441% (+/-7.11%)
bm_fannkuch.py        74.96 ->      76.16 :     +1.20 =  +1.601% (+/-1.80%)
bm_fft.py         166682.99 ->  168221.86 :  +1538.87 =  +0.923% (+/-4.20%)
bm_float.py       233415.23 ->  265524.90 : +32109.67 = +13.756% (+/-2.57%)
bm_hexiom.py         628.59 ->     734.17 :   +105.58 = +16.796% (+/-1.39%)
bm_nqueens.py     225418.44 ->  232926.45 :  +7508.01 =  +3.331% (+/-3.10%)
bm_pidigits.py      6322.00 ->    6379.52 :    +57.52 =  +0.910% (+/-5.62%)
misc_aes.py        20670.10 ->   27223.18 :  +6553.08 = +31.703% (+/-1.56%)
misc_mandel.py    138221.11 ->  152014.01 : +13792.90 =  +9.979% (+/-2.46%)
misc_pystone.py    85032.14 ->  105681.44 : +20649.30 = +24.284% (+/-2.25%)
misc_raytrace.py   19800.01 ->   23350.73 :  +3550.72 = +17.933% (+/-2.79%)

In summary, compared to MICROPY_OPT_CACHE_MAP_LOOKUP_IN_BYTECODE, the new
MICROPY_OPT_LOAD_ATTR_FAST_PATH and MICROPY_OPT_MAP_LOOKUP_CACHE options:
- are simpler;
- take less code size;
- are faster (generally);
- work with code generated by the native emitter;
- can be used on embedded targets with a small and constant RAM overhead;
- allow the same .mpy bytecode to run on all targets.

See #7680 for further discussion.  And see also #7653 for a discussion
about simplifying mpy-cross options.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2021-09-16 16:04:03 +10:00
Jim Mussared
11ef8f22fe py/map: Add an optional cache of (map+index) to speed up map lookups.
The existing inline bytecode caching optimisation, selected by
MICROPY_OPT_CACHE_MAP_LOOKUP_IN_BYTECODE, reserves an extra byte in the
bytecode after certain opcodes, which at runtime stores a map index of the
likely location of this field when looking up the qstr.  This scheme is
incompatible with bytecode-in-ROM, and doesn't work with native generated
code.  It also stores bytecode in .mpy files which is of a different format
to when the feature is disabled, making generation of .mpy files more
complex.

This commit provides an alternative optimisation via an approach that adds
a global cache for map offsets, then all mp_map_lookup operations use it.
It's less precise than bytecode caching, but allows the cache to be
independent and external to the bytecode that is executing.  It also works
for the native emitter and adds a similar performance boost on top of the
gain already provided by the native emitter.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2021-09-16 16:02:19 +10:00
Jim Mussared
7b89ad8dbf py/vm: Add a fast path for LOAD_ATTR on instance types.
When the LOAD_ATTR opcode is executed there are quite a few different cases
that have to be handled, but the common case is accessing a member on an
instance type.  Typically, built-in types provide methods which is why this
is common.

Fortunately, for this specific case, if the member is found in the member
map then there's no further processing.

This optimisation does a relatively cheap check (type is instance) and then
forwards directly to the member map lookup, falling back to the regular
path if necessary.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2021-09-16 16:02:15 +10:00
Jim Mussared
01374d941f py/mpconfig.h: Define initial templates for "feature levels".
This is the beginning of a set of changes to simplify enabling/disabling
features.  The goals are:
- Remove redundancy from mpconfigport.h (never set a value to the default
  -- make it clear exactly what's being enabled).
- Improve consistency between ports.  All "similar" ports (i.e. approx same
  flash size) should get the same features.
- Simplify mpconfigport.h -- just get default/sensible options for the size
  of the port.
- Make it easy for defining constrained boards (e.g. STM32F0/L0), they can
  just set a lower level.

This commit makes a step towards this and defines the "core" level as the
current default feature set, and a "minimal" level to turn off everything.
And a few placeholder levels are added for where the other ports will
roughly land.

This is a no-op change for all ports.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2021-09-16 13:19:11 +10:00
Damien George
426785a19e py/emitnative: Ensure load_subscr does not clobber existing REG_RET.
Fixes issue #7782, and part of issue #6314.

Signed-off-by: Damien George <damien@micropython.org>
2021-09-13 22:30:24 +10:00
Damien George
e6850838cd py/parse: Simplify parse nodes representing a list.
This commit simplifies and optimises the parse tree in-memory
representation of lists of expressions, for tuples and lists, and when
tuples are used on the left-hand-side of assignments and within del
statements.  This reduces memory usage of the parse tree when such code is
compiled, and also reduces the size of the compiler.

For example, (1,) was previously the following parse tree:

    expr_stmt(5) (n=2)
      atom_paren(45) (n=1)
        testlist_comp(146) (n=2)
          int(1)
          testlist_comp_3b(149) (n=1)
            NULL
      NULL

and with this commit is now:

    expr_stmt(5) (n=2)
      atom_paren(45) (n=1)
        testlist_comp(146) (n=1)
          int(1)
      NULL

Similarly, (1, 2, 3) was previously:

    expr_stmt(5) (n=2)
      atom_paren(45) (n=1)
        testlist_comp(146) (n=2)
          int(1)
          testlist_comp_3c(150) (n=2)
            int(2)
            int(3)
      NULL

and is now:

    expr_stmt(5) (n=2)
      atom_paren(45) (n=1)
        testlist_comp(146) (n=3)
          int(1)
          int(2)
          int(3)
      NULL

Signed-off-by: Damien George <damien@micropython.org>
2021-09-10 14:09:44 +10:00
Damien George
af64c2ddbd extmod/machine_pwm: Factor out machine.PWM bindings to common code.
This commit refactors machine.PWM and creates extmod/machine_pwm.c.  The
esp8266, esp32 and rp2 ports all use this and provide implementations of
the required PWM functionality.  This helps to reduce code duplication and
keep the same Python API across ports.

This commit does not make any functional changes.

Signed-off-by: Damien George <damien@micropython.org>
2021-09-04 16:31:17 +10:00
Damien George
d41f6dde56 extmod/modonewire: Make _onewire module configurable via macro option.
Signed-off-by: Damien George <damien@micropython.org>
2021-09-02 13:11:23 +10:00
Damien George
afe0634c98 extmod/machine_spi: Make SoftSPI configurable via macro option.
Signed-off-by: Damien George <damien@micropython.org>
2021-09-02 13:11:23 +10:00
Damien George
122d901ef1 extmod/machine_i2c: Make SoftI2C configurable via macro option.
The zephyr port doesn't support SoftI2C so it's not enabled, and the legacy
I2C constructor check can be removed.

Signed-off-by: Damien George <damien@micropython.org>
2021-09-02 13:11:23 +10:00
Damien George
7c54b64280 all: Bump version to 1.17.
Signed-off-by: Damien George <damien@micropython.org>
2021-09-02 00:07:13 +10:00
Jim Mussared
b51e7e9d01 stm32: Disable computed goto on constrained boards.
Saves ~1kiB.  Add comment to this effect to mpconfig.h.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2021-08-20 20:18:52 +10:00
Jim Mussared
85adc25558 py/mkrules.mk: Do submodule sync in "make submodules".
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2021-08-19 22:53:44 +10:00
Jim Mussared
e64cda5295 stm32: Add implementation of machine.bitstream.
Hand-written version for M0, and cycle-counter version for everything else.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2021-08-19 22:50:32 +10:00
Jim Mussared
870000f35b extmod: Add machine.bitstream.
This is a generic API for synchronously bit-banging data on a pin.

Initially this adds a single supported encoding, which supports controlling
WS2812 LEDs.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2021-08-19 22:50:11 +10:00
Jim Mussared
5555f147df py/lexer: Clear fstring_args vstr on lexer free.
This was missed in 692d36d779.  It's not
strictly necessary as the GC will clean it anyway, but it's good to
pre-emptively gc_free() all the blocks used in lexing/parsing.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2021-08-19 17:31:02 +10:00
Jim Mussared
692d36d779 py: Implement partial PEP-498 (f-string) support.
This implements (most of) the PEP-498 spec for f-strings and is based on
https://github.com/micropython/micropython/pull/4998 by @klardotsh.

It is implemented in the lexer as a syntax translation to `str.format`:
  f"{a}" --> "{}".format(a)

It also supports:
  f"{a=}" --> "a={}".format(a)

This is done by extracting the arguments into a temporary vstr buffer,
then after the string has been tokenized, the lexer input queue is saved
and the contents of the temporary vstr buffer are injected into the lexer
instead.

There are four main limitations:
- raw f-strings (`fr` or `rf` prefixes) are not supported and will raise
  `SyntaxError: raw f-strings are not supported`.

- literal concatenation of f-strings with adjacent strings will fail
    "{}" f"{a}" --> "{}{}".format(a)    (str.format will incorrectly use
                                         the braces from the non-f-string)
    f"{a}" f"{a}" --> "{}".format(a) "{}".format(a) (cannot concatenate)

- PEP-498 requires the full parser to understand the interpolated
  argument, however because this entirely runs in the lexer it cannot
  resolve nested braces in expressions like
    f"{'}'}"

- The !r, !s, and !a conversions are not supported.

Includes tests and cpydiffs.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
2021-08-14 16:58:40 +10:00