python/exercises/complex-numbers/.meta/template.j2

from __future__ import division
import math

{% extends "master_template.j2" -%}
{%- set imports = ["ComplexNumber"] -%}

{%- macro translate_math(item) -%}
{{ item | replace("pi", "math.pi") | replace("e", "math.e") | replace("ln", "math.log") }}
{%- endmacro %}

{%- macro formatValue(val) -%}
{% if val is iterable and val is not string -%}
    ComplexNumber({% for part in val %}{{ translate_math(part) }}{{ "," if not loop.last }}{% endfor %})
{%- else -%}
    {{ translate_math(val) }}
{%- endif -%}
{%- endmacro -%}

{%- macro smartAssert(case) -%}
self.assert
{%- if case["property"] in ["exp", "div"] -%}Almost
{%- elif case["property"] == "eq" and not case["expected"] -%}Not
{%- endif -%}Equal
{%- endmacro -%}

{%- macro operator(prop) -%}
{% if prop == "add" -%}+
{%- elif prop == "sub" -%}-
{%- elif prop == "mul" -%}*
{%- elif prop == "div" -%}/
{%- endif -%}
{%- endmacro -%}

{% macro test_case(case) -%}
    def test_{{ case["description"] | to_snake }}(self):
        {% set input = case["input"] -%}
        {%- set prop = case["property"] -%}
        {%- set is_callable = prop not in ["real", "imaginary"] -%}
        {%- set is_builtin = prop in ["abs"] -%}
        {%- set expected = formatValue(case["expected"]) -%}
        {%- if input|length == 1 -%}
            {%- set z = formatValue(input["z"]) -%}
            {% if is_builtin -%}
                {%- set actual = prop ~ "(" ~ z ~ ")" -%}
            {%- else -%}
                {%- set actual = z ~ "." ~ prop -%}
                {%- if is_callable -%}
                    {%- set actual = actual ~ "()" -%}
                {%- endif -%}
            {%- endif -%}
        {%- else -%}
            {%- set z1 = formatValue(input["z1"]) -%}
            {%- set z2 = formatValue(input["z2"]) -%}
            {%- if prop == "eq" -%}
                {%- set actual = z1 -%}
                {%- set expected = z2 -%}
            {%- else -%}
                {%- set actual = z1 ~ operator(prop) ~ z2 -%}
            {% endif -%}
        {%- endif -%}
        {{ smartAssert(case) }}({{ actual }}, {{expected}})
{%- endmacro %}