starknet_os: os resources test - add emit event

[dorimedini-starkware]

No description provided.

[dorimedini-starkware]

• starknet_os: os resources test - add send_message_to_l1 #14143 : 2 dependent PRs (#14144 , #14153 )
• starknet_os: os resources test - add replace_class #14142
• starknet_os: os resources test - support virtual builtins, add sha256 #14141
• starknet_os: define sha256 batch resources constants #14140
• starknet_os: os resources test - add keccak #14139
• starknet_os: os resources test - add 3 more syscalls #14138
• starknet_os: os resources test - remove all fee transfer syscalls #14137
• starknet_os: os resources test - add emit event #14136 👈 (View in Graphite)
• starknet_os: os resources test - add meta tx #14135
• starknet_os: os resources test - measure linear factor, add deploy #14134
• starknet_os: os resources test - library call #14129
• starknet_os: initial test, measure call contract resources #14128
• blockifier_test_utils: add option to deploy from zero in test accounts #14258
• starknet_os_flow_tests: helper function to declare explicit classes #14257
• starknet_os: os resources test - create fixed deployable account #14173
• main

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[reviewable-StarkWare]

This change is 

[cursor]

PR Summary

Medium Risk
Changes published syscall OS resource constants used for fee/gas estimation; incorrect values would affect transaction costing across the network stack.

Overview
EmitEvent is now part of the OS syscall resource regression harness instead of being skipped as unmeasurable.

The measurement contract invokes emit_event_syscall with keys [5] and data [7]. The OS flow test asserts that event and strips the trailing EmitEvent trace from fee transfer so syscall accounting stays correct. EmitEvent n_steps in versioned constants 0.14.4 is set to 47 (was 61), with the constants diff regression file updated accordingly.

execution_flavors_test folds measured EmitEvent steps into expected gas for the balance-too-low transfer scenario. Inner-call resource deduction in the OS resources test is slightly refactored so filter_unused_builtins always runs on the result.

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[dorimedini-starkware]

@dorimedini-starkware made 2 comments and resolved 2 discussions.
Reviewable status: 2 of 5 files reviewed, 2 unresolved discussions (waiting on yoavGrs and Yoni-Starkware).

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crates/starknet_os_flow_tests/src/os_resources_test.rs line 220 at r1 (raw file):

Previously, Yoni-Starkware (Yoni) wrote…

You can run this tx with trivial fee bounds and make this test a bit cleaner

fixed properly in the next PR. your way could also work but I don't want to break if for some reason we want to avoid trivial resource bounds

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crates/starknet_os_flow_tests/src/os_resources_test.rs line 227 at r2 (raw file):

Previously, yoavGrs wrote…

IMO you can omit these lines.
The while loop ensures that if EmitEvent is a measurable syscall, it appears only once more.

this is fixed properly in the next PR

[yoavGrs]

@yoavGrs reviewed 3 files and all commit messages.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on Yoni-Starkware).

[github-actions]

Artifacts upload workflows:

• Started at 2026-06-07T12:34:01Z
• Started at 2026-06-07T12:48:57Z
• Started at 2026-06-07T12:52:14Z

[dorimedini-starkware]

@dorimedini-starkware made 1 comment.
Reviewable status: 3 of 7 files reviewed, 3 unresolved discussions (waiting on dorimedini-starkware, yoavGrs, and Yoni-Starkware).

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crates/blockifier/src/transaction/execution_flavors_test.rs line 910 at r5 (raw file):

            )
            + u64_from_usize(get_const_syscall_resources(SyscallSelector::EmitEvent).n_steps)
            + 3527)

3527 == 3588 - 61, where 61 is the old step cost of EmitEvent

Code quote:

3527

[Yoni-Starkware]

@Yoni-Starkware reviewed 5 files and all commit messages, made 1 comment, and resolved 1 discussion.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on dorimedini-starkware and yoavGrs).

[dorimedini-starkware]

@dorimedini-starkware resolved 2 discussions.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on dorimedini-starkware).