Step Matchers

behave provides 3 step matchers:

1. “parse” (ParseMatcher) by using the parse module
2. “cfparse” (extended ParseMatcher) that supports the cardinality field syntax
3. “re” (RegexMatcher) that uses regular expressions for matching parameters

The “parse” matcher is the default step matcher. It is more commonly used because it is:

• easier to use, read and understand
• provides data types support with predefined and user-defined types
• reuses (hidden) regular expressions better by using data types (as alias)
• hides regular expression complexity

The “cfparse” matcher extends the “parse” patcher (and is rather new). It is intended to superceed the “parse” matcher as default matcher. It has the following features:

• extended parser that understands the cardinality field syntax
• automatically creates missing type converters for fields with cardinality field part
• based on parse-type

The “re” matcher is used for the following reasons. It:

• addresses some cases that cannot be solved otherwise (currently)
• is backward compatible to cucumber (uses regular expressions)
• is less ambiguous compared to the “parse” matcher (currently)

It should be noted that all step matchers use regular expressions. But most of the regular expressions (and their complexity) is hidden by the parse module (or its cousin).

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Contents:

• Using the Step Matchers
• Use the Parse Matcher (parse)
• Use the Regular Expression Matcher (re)
• Use Optional Part in Step Definitions
• Use Multi-Methods in Step Definitions
• Regular Expressions