SKILL Tools

Tools to ease working with SKILL and SKILL++ in Cadence Virtuoso. The main feature of interest is the unit testing framework in the folder qtest. This repo contains the code that I use regularly in my PhD so it's also available in case anyone finds any use for it. There's not a lot of SKILL code in the wild beyond the Cadence forums.

Project Structure

Folder	Namespace	Purpose
circuits	qub	Circuit analysis
design_environment	qub	Manipulating the Cadence Virtuoso design environment
geometry	qub	Geometry calculations
ocean	qub	Processing simulation results
pcell	qub	Generating custom PCells
qtest	qtest	Unit testing.
std	qub	A "standard library" of useful functions.
inductor_generator	qub	Inductor PCell generation.

Importing the project

Import from source

1. Clone the skill_tools github repo from: https://github.com/MatthewLoveQUB/SKILL_Tools
2. Create the environment variable QUB_CODE_REPO_DIR and point it at the repo root directory.
3. Add the src folder to the SKILL path:

   (setSkillPath (append (getSkillPath) (list (strcat (getShellEnvVar "QUB_CODE_REPO_DIR") "/src/")))).

4. Run the following in the Virtuoso command line to load all the modules:

   (load (strcat (getShellEnvVar "QUB_CODE_REPO_DIR") "/src/init.ils"))

5. If the inductor PCell code is to be used, this code library needs to be re-added using libInit.il for the Virtuoso library that the PCell resides in or else stream-out will fail.

Build and install into Conda

Currently a

0. You will first need a conda environment. Here are some instructions: https://docs.conda.io/projects/conda/en/latest/user-guide/getting-started.html

Unit Testing

The unit testing framework is modelled after Python's unittest module and provides a basic set of assertions for testing your code.

Example Test

The test is run by calling load on the file containing the test.

(qtest::runSuites
  (qtest::TestSuite ((f qub:::join_lists))
    (qtest::TestCase join_three_lists
      (qtest::assertEqual (list "X" 2 3 4 5 6)
                           (f (list (list 1 2) (list 3 4) (list 5 6))))))
  (qtest::TestSuite ((f qub::flatten_list))
    (qtest::TestCase normal_use
      (qtest::assertEqual (list 1 2 3 4 5 6 7)
                           (f (list 1 2 (list 3 (list 4 (list 5 6) 7))))))))

(load "./code/src/std/test_lists.ils")
1 of 2 tests passed (1 failures) (0 skipped) (0 expected failures)
Test: join_three_lists
Result: Fail
 Message: No msg.
 Inputs: (list("X" 2 3 4 5 6) (f list(list(1 2) list(3 4) list(5 6))))
 Evaluated Inputs: (("X" 2 3 4 5 6) (1 2 3 4 5 6))

Main Functions and Macros

qtest::runAllTests

Parameter(s)	Side Effect(s)
Directory (string)	Calls load on all files prefixed with test_ in the directory

Takes a folder path and loads all modules prefixed with test_.

qtest::TestCase

Parameters(s)	Keyword Parameters	Output(s)
Test Name (unquoted symbol)	skip (bool)	List of the test name symbol and the function object
body	expect_fail (bool)

Represents a single test. Can contain any code but must return the result of an assertion function. The test name is contained in a list with the function object so tests don't pollute the top level namespace.

Skipping a test

To mark a test to be skipped, set the skip keyword argument to true.

Marking a test that you expect to fail

Set the expect_fail keyword argument to true. If the test passes it will count as a pass but if it fail it will not be recorded as a fail.

qtest::TestSuite

Parameter(s)	Output(s)
Test Cases	List containing lists returned by qtest::TestCase

A collection of test cases. A suite should be used to test a single function or method.

qtest::runSuites

Parameter(s)	Side Effect(s)
Any number of Test Suites	Prints the results of the tests

Test suites should be written in the body of this macro. When the module file is loaded in Virtuoso, the tests are initialised and the results are printed in the CIW.

Assertions

Each assertion takes a keyword argument msg which is printed if the test fails.

qtest::assertEqual

Parameter(s)	Keyword Parameters	Output(s)
a	msg (string)	qtest::Result
b

Checks if two objects are equal. Uses the qub::equal method to allow you to implement equality for your own objects as well as numbers, strings etc.

qtest::assertNotEqual

Parameter(s)	Keyword Parameters	Output(s)
a	msg (string)	qtest::Result
b

Checks if two objects are not equal. Uses the qub::notEqual method to allow you to implement equality for your own objects as well as numbers, strings etc.

qtest::assertTrue

Parameter(s)	Keyword Parameters	Output(s)
a	msg (string)	qtest::Result

Checks that the argument is true.

qtest::assertNil

Parameter(s)	Keyword Parameters	Output(s)
a	msg (string)	qtest::Result

Checks that the argument is nil.

qtest::assertEq

Parameter(s)	Keyword Parameters	Output(s)
a	msg (string)	qtest::Result
b

Both arguments are the same object.

qtest::assertNotEq

Parameter(s)	Keyword Parameters	Output(s)
a	msg (string)	qtest::Result
b

The arguments are different objects.

qtest::assertMember

Parameter(s)	Keyword Parameters	Output(s)
value	msg (string)	qtest::Result
list

The object is a member of the list.

qtest::assertNotMember

Parameter(s)	Keyword Parameters	Output(s)
value	msg (string)	qtest::Result
list

The object is not a member of the list.

qtest::assertIsInstance

Parameter(s)	Keyword Parameters	Output(s)
Object	msg (string)	qtest::Result
Quoted Class

The object is an instance of the class.

qtest::assertNotIsInstance

Parameter(s)	Keyword Parameters	Output(s)
Object	msg (string)	qtest::Result
Quoted Class

The object is not an instance of the class.

qtest::assertRaises

Parameter(s)	Keyword Parameters	Output(s)
Function Call	msg (string)	qtest::Result

Checks that the expression raises an error using error. It may not catch other errors within the expression.

qtest::assertAlmostEqual

Parameter(s)	Keyword Parameters	Output(s)
a	msg (string)	qtest::Result
b

Checks that two floats are almost equal. Uses qub::almostEqual which is a port of Python's math.isclose and uses the same optional arguments.

qtest::assertNotAlmostEqual

Parameter(s)	Keyword Parameters	Output(s)
a	msg (string)	qtest::Result
b

Checks that two floats are not almost equal.

Standard Library Functions and Macros

qub::checkType

Parameters	Side Effects
Object	Throws an error if the object is of the expected type.
Quoted Class Name

For implementing run-time type checking in functions.

qub::equal

Parameters	Result
a	Bool
b

A generic function for implementing equality for your own types.

qub::nequal

Parameters	Result
a	Bool
b

A generic function for implementing inequality for your own types.

qub::allEqual

Parameters	Result
@rest values	bool

Checks if all values are equal. It uses qub::equal for checking equality.

qub::listFileRec

Parameter	Result
Path (string)	List of files in the directory

Recursively searches the path for all files. It ignores all dotted directories.

qub::foldl

Paramater	Result
fn(accumulator value)	The "folded" value
Initial Value
List of Values

The HaskellWiki can probably explain this better than I could.

qub::foldr

The same as qub::foldl but it calls reverse on the list before it processes it.

qub::sum

Sums a list of numbers

qub:::lcmp

An implementation of python's list comprehensions. The predicate is optional.

>>>(qub:::lcmp (times x 2) for x in (list 1 2 3 4) if (evenp x))
(4 8)

qub::joinLists

Paramater	Result
List of lists	A single list of the values within the input lists

qub::range

Keyword parameters	Result
start	List of integers
stop
step

A port of python's range function.

>>>(qub::range ?start 0 ?stop 20 ?step 3)
(0 3 6 9 12
    15 18
)

qub::almostEqual

Parameters	Keyword Parameters	Result
a	rel_tol	Bool
b	abs_tol

Checks that two values are almost equal. This is a generic function and can be applied to your own types. The method specialised on numbers is a port of Python's math.isclose and uses the same optional arguments.

rel_tol is the relative tolerance. 0.05 would be a 5% relative tolerance. abs_tol is the absolute tolerance.

qub::startsWith

Parameters	Result
string	Bool
prefix (string)

Checks if a string begins with a particular prefix