review: test: add test for Substitution.insertAllConstructors

[Rohitesh-Kumar-Jain]

#1818

Hi, I have added a new test for insertAllConstructor method of the Substitution class, following are the features of this test:

1. This new test is killing this mutation :

2. This method had some code coverage but, the test strength and mutation coverage was zero, now code coverage has improved and the mutation has been killed by this new test.

3. this test improves code coverage, mutation converge and test strength all from 0% to 100% for insertConstructor method.

Link to #3967

[slarse]

Hi @Rohitesh-Kumar-Jain,

Just an FYI I'm on vacation and won't be reviewing pull requests until monday. Perhaps @nharrand or @monperrus can find the time to look at this, but otherwise I'll get to it on Monday. Feel free to submit more PRs in parallel if you'd like.

[slarse]

LGTM