alecthomas / importmagic

A Python library for finding unresolved symbols in Python code, and the corresponding imports
BSD 2-Clause "Simplified" License
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Import Magic image

The goal of this package is to be able to automatically manage imports in Python. To that end it can:

It was originally written for the Sublime Text 2 Python Import Magic plugin.

Example of use in Sublime Text 2 plugin

Example of Import Magic at work

Using the library

Getting index from cache:

index = importmagic.SymbolIndex()
index.get_or_create_index(name='foo', paths=sys.path)

Build an index:

index = importmagic.SymbolIndex()
index.build_index(sys.path)
with open('index.json') as fd:
    index.serialize(fd)

Load an existing index:

with open('index.json') as fd:
    index = SymbolIndex.deserialize(fd)

Find unresolved and unreferenced symbols:

scope = importmagic.Scope.from_source(python_source)
unresolved, unreferenced = scope.find_unresolved_and_unreferenced_symbols()

Print new import block:

start_line, end_line, import_block = importmagic.get_update(python_source, index, unresolved, unreferenced)

Update source code with new import blocks:

python_source = importmagic.update_imports(python_source, index, unresolved, unreferenced)

For more fine-grained control over what symbols are imported, the index can be queried directly:

imports = importmagic.Imports(index, python_source)
imports.remove(unreferenced)

for symbol in unresolved:
    for score, module, variable in index.symbol_scores(symbol):
        if variable is None:
            imports.add_import(module)
        else:
            imports.add_import_from(module, variable)
        break

python_source = imports.update_source()

Configuration

Configuring import styles

  1. Using importmagic.Imports.
imports = importmagic.Imports.set_style(multiline='backslash', max_columns=80, indent_with_tabs=True)

multiline takes backlslash or parentheses.

  1. From setup.cfg

Add configuration to setup.cfg

[importmagic]
multiline = 'parentheses'
max_columns = 120
indent_with_tabs = 1

and pass root directory to importmagic

imports = importmagic.Imports(root_dir='/foo/bar/')