nushell/crates
Andreas Källberg 6df001f72d
Prevent cubic time on nested parentheses (#10467)
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# Description
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When parse_range get an item like ((((1..2)))) it would try to parse
"((((1" with a long chain of recursive parsers, namely:
- parse_value
- parse_paren_expr
- parse_full_cell_path
- parse_block
- parse_pipeline
- parse_builtin_commands
- parse_expression
- parse_math_expression
- parse_value
- ...

where `parse_paren_expr` calls `parse_range` in turn. Because at any
time in the chain `parse_paren_expr` can call `parse_range`, which will
then continue the chain, we get quadratic number of function calls, each
linear on the size of the input

By checking with the lexer that the parens are matched, we prevent the
long chain from being called on unmatched braces. Now, this is still
more quadratic than it needs to be, to fix that, we should process
parens only once, instead of on each recursive call

# User-Facing Changes
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helps us keep track of breaking changes. -->
Speed improvements in some edge cases

# Tests + Formatting
Not sure how to test this, maybe I could add a benchmark
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# Other notes
Found using the fuzzer, by setting a timeout on max run-time. It also
found a stack-overflow on too many parentheses, which this doesn't fix.
2023-09-23 04:24:35 +12:00
..
nu-cli Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu-cmd-base Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu-cmd-dataframe Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu-cmd-extra Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu-cmd-lang Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu-color-config Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu-command Improve select row perf for large N (#10355) 2023-09-21 23:51:13 +02:00
nu-engine Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu-explore Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu-glob Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu-json Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu-parser Prevent cubic time on nested parentheses (#10467) 2023-09-23 04:24:35 +12:00
nu-path Fix tilde-expansion for multi-byte unicode chars (#10434) 2023-09-21 04:04:28 +12:00
nu-plugin Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu-pretty-hex Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu-protocol Split up nu-protocol/src/engine/engine_state.rs (#10368) 2023-09-21 22:53:36 +02:00
nu-std Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu-system Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu-table Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu-term-grid Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu-test-support Simplify nu! test macros. (#10403) 2023-09-21 20:11:56 +02:00
nu-utils nu-table: Add table option --abbreviated (#10399) 2023-09-20 12:59:08 -05:00
nu_plugin_custom_values Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu_plugin_example Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu_plugin_formats Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu_plugin_gstat Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu_plugin_inc Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
nu_plugin_python remove vectorize_over_list from python plugin (#9905) 2023-08-03 16:46:48 +02:00
nu_plugin_query Bump to 0.85.1 development version (#10431) 2023-09-20 18:38:42 +12:00
README.md Remove old nushell/merge engine-q 2022-02-07 14:54:06 -05:00

Nushell core libraries and plugins

These sub-crates form both the foundation for Nu and a set of plugins which extend Nu with additional functionality.

Foundational libraries are split into two kinds of crates:

  • Core crates - those crates that work together to build the Nushell language engine
  • Support crates - a set of crates that support the engine with additional features like JSON support, ANSI support, and more.

Plugins are likewise also split into two types:

  • Core plugins - plugins that provide part of the default experience of Nu, including access to the system properties, processes, and web-connectivity features.
  • Extra plugins - these plugins run a wide range of different capabilities like working with different file types, charting, viewing binary data, and more.