README.md

Semantics-tester

This software implements property-based cross-testing of Erlang (implemented in the K framework) and Core Erlang (implemented in Coq) semantics.

Dependencies:

xpath
    apt install libxml-xpa
Erlang/OTP (>22)
    https://www.erlang.org/downloads
Erlang QuickCheck (preferably Quviq, compatibility with PropEr or Triq is not tested)
    http://www.quviq.com/downloads/
Coq (>8.12)
    https://github.com/coq/coq/releases/tag/V8.12.0
K framework (3.6)
    https://github.com/kframework/k-legacy/releases/tag/v3.6

Supplied dependencies:

eqc (Erlang BEAM)
generator (Erlang BEAM)

Setup

1. Compile the semantics:

• Run kompile erl.k in the erlang-semantics/erl_env and erlang-semantics/erl_env_traced. These folders include the small-step (reduction-stlye) semantics for Erlang, with and without rewrite rule tracing.
• Build the Core Erlang Formalisation project (https://github.com/harp-project/Core-Erlang-Formalization/blob/master/README.md)

2. Build the the tester software with make

Usage

• make check: executes the test suite
• ./scripts.erl <Erlang file/path>: runs the Erlang code, and both semantics for the same code
• ./scripts.erl random <num>: runs <num> random tests or stops after finding an error

In the scripts.erl file there are several options:

• With TRACING the coverage measurment can be turned on/off
• With SHRINKING the shrinking of found counterexamples can be turned on/off
• With GHC_EXPORT the extraction of the Core Erlang semantics can be turned on/off
• With GEN_REC_LIMIT the generated program size can be customized
• With GEN_SIZE the generated base value (e.g. variable names, numbers) sizes can be customized
• With GEN_REC_WEIGHT the propability of using recursive generation rule can be set