def interpolate()

in otava/util.py [0:0]


def interpolate(s: str, vars: Dict[str, List[str]]) -> List[str]:
    """
    Replaces all occurrences of %{VARIABLE} with respective variable values looked up in the
    vars dictionary. A variable is allowed to have more than one value assigned –
    in this case one result string is returned per each combination of variable values.

    Example:
    s = "name:%{NAME}"
    vars = { "NAME": ["foo", "bar"] }
    result = ["name:foo", "name:bar"]
    """
    match = re.search("%{(\\w+)}", s)
    if match:
        var_name = match.group(1)
        values = vars[var_name]
        start, end = match.span(0)
        before = s[0:start]
        after = s[end:]
        result = []
        remaining = interpolate(after, vars)
        for suffix in remaining:
            for v in values:
                result.append(before + v + suffix)
        return result
    else:
        return [s]