stringmap.py

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from collections import Counter

STRING_MATCHING_RATIO_JAVASCRIPT = 0.7
SMALL_FILE_STRING_THRESHOLD_JAVASCRIPT = 10
STRING_MATCHING_RATIO_JAVASCRIPT_SMALL_FILE = 0.5


def match_source_strings_to_deployed(source_strings, deployed_strings):
    """
    Compute the similarity between source and deployed string literals and
    return whether they match based on matching threshold.
    """
    common_strings_ratio = 0
    is_match = False
    deployed_strings_set = set(deployed_strings)
    source_strings_set = set(source_strings)
    source_strings_count = len(source_strings)
    deployed_strings_count = len(deployed_strings)
    total_strings_count = source_strings_count + deployed_strings_count
    source_strings_counter = Counter(source_strings)
    deployed_strings_counter = Counter(deployed_strings)

    common_strings = source_strings_set.intersection(deployed_strings_set)
    total_common_strings_count = sum(
        [
            source_strings_counter.get(string, 0)
            + deployed_strings_counter.get(string, 0)
            for string in common_strings
        ]
    )

    if total_common_strings_count:
        common_strings_ratio = total_common_strings_count / total_strings_count

    if common_strings_ratio > STRING_MATCHING_RATIO_JAVASCRIPT:
        is_match = True
    elif (
        source_strings_count > SMALL_FILE_STRING_THRESHOLD_JAVASCRIPT
        and common_strings_ratio > STRING_MATCHING_RATIO_JAVASCRIPT_SMALL_FILE
    ):
        is_match = True

    return is_match, common_strings_ratio