🐛 properly handle timing literals in QASM parser

[burgholzer]

Description

This PR fixes a bug in the QASM parser that would treat timing literal suffixes as individual tokens, which can lead to strange errors with gate declarations whose name matches a timing literal suffix, e.g., ms. Timing literals are now properly treated and do not lead to clashes.

In the process, it was noticed that the Python import of long QASM strings would fail due to pathlib throwing an OSError for too long paths. This is now fixed by short circuiting if the path is too long.

Fixes #723

Checklist:

• [x] The pull request only contains commits that are related to it.
• [x] I have added appropriate tests and documentation.
• [x] I have made sure that all CI jobs on GitHub pass.
• [x] The pull request introduces no new warnings and follows the project's style guidelines.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 92.2%. Comparing base (11a7d49) to head (896257d). Report is 1 commits behind head on main.

Additional details and impacted files

[](https://app.codecov.io/gh/cda-tum/mqt-core/pull/724?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=cda-tum) ```diff @@ Coverage Diff @@ ## main #724 +/- ## ======================================= + Coverage 92.1% 92.2% +0.1% ======================================= Files 125 125 Lines 13757 13739 -18 Branches 2150 2158 +8 ======================================= + Hits 12671 12678 +7 + Misses 1086 1061 -25 ``` | [Flag](https://app.codecov.io/gh/cda-tum/mqt-core/pull/724/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=cda-tum) | Coverage Δ | | |---|---|---| | [cpp](https://app.codecov.io/gh/cda-tum/mqt-core/pull/724/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=cda-tum) | `92.0% <100.0%> (+0.1%)` | :arrow_up: | | [python](https://app.codecov.io/gh/cda-tum/mqt-core/pull/724/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=cda-tum) | `99.7% <100.0%> (+<0.1%)` | :arrow_up: | | [Files with missing lines](https://app.codecov.io/gh/cda-tum/mqt-core/pull/724?dropdown=coverage&src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=cda-tum) | Coverage Δ | | |---|---|---| | [...clude/mqt-core/ir/parsers/qasm3\_parser/Scanner.hpp](https://app.codecov.io/gh/cda-tum/mqt-core/pull/724?src=pr&el=tree&filepath=include%2Fmqt-core%2Fir%2Fparsers%2Fqasm3_parser%2FScanner.hpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=cda-tum#diff-aW5jbHVkZS9tcXQtY29yZS9pci9wYXJzZXJzL3Fhc20zX3BhcnNlci9TY2FubmVyLmhwcA==) | `71.4% <ø> (ø)` | | | [include/mqt-core/ir/parsers/qasm3\_parser/Token.hpp](https://app.codecov.io/gh/cda-tum/mqt-core/pull/724?src=pr&el=tree&filepath=include%2Fmqt-core%2Fir%2Fparsers%2Fqasm3_parser%2FToken.hpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=cda-tum#diff-aW5jbHVkZS9tcXQtY29yZS9pci9wYXJzZXJzL3Fhc20zX3BhcnNlci9Ub2tlbi5ocHA=) | `98.2% <100.0%> (-0.1%)` | :arrow_down: | | [src/ir/parsers/qasm3\_parser/Parser.cpp](https://app.codecov.io/gh/cda-tum/mqt-core/pull/724?src=pr&el=tree&filepath=src%2Fir%2Fparsers%2Fqasm3_parser%2FParser.cpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=cda-tum#diff-c3JjL2lyL3BhcnNlcnMvcWFzbTNfcGFyc2VyL1BhcnNlci5jcHA=) | `92.6% <100.0%> (-0.1%)` | :arrow_down: | | [src/ir/parsers/qasm3\_parser/Scanner.cpp](https://app.codecov.io/gh/cda-tum/mqt-core/pull/724?src=pr&el=tree&filepath=src%2Fir%2Fparsers%2Fqasm3_parser%2FScanner.cpp&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=cda-tum#diff-c3JjL2lyL3BhcnNlcnMvcWFzbTNfcGFyc2VyL1NjYW5uZXIuY3Bw) | `97.0% <100.0%> (+0.1%)` | :arrow_up: | | [src/mqt/core/\_\_init\_\_.py](https://app.codecov.io/gh/cda-tum/mqt-core/pull/724?src=pr&el=tree&filepath=src%2Fmqt%2Fcore%2F__init__.py&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=cda-tum#diff-c3JjL21xdC9jb3JlL19faW5pdF9fLnB5) | `100.0% <100.0%> (ø)` | | ... and [16 files with indirect coverage changes](https://app.codecov.io/gh/cda-tum/mqt-core/pull/724/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=cda-tum)