#!/usr/bin/env python
from nose.tools import *
import networkx as nx
import os,tempfile

class TestLEDA(object):

    def test_parse_leda(self):
        data="""#header section	  \nLEDA.GRAPH \nstring\nint\n-1\n#nodes section\n5 \n|{v1}| \n|{v2}| \n|{v3}| \n|{v4}| \n|{v5}| \n\n#edges section\n7 \n1 2 0 |{4}| \n1 3 0 |{3}| \n2 3 0 |{2}| \n3 4 0 |{3}| \n3 5 0 |{7}| \n4 5 0 |{6}| \n5 1 0 |{foo}|"""
        G=nx.parse_leda(data)
        G=nx.parse_leda(data.split('\n'))
        assert_equal(sorted(G.nodes()),
                     ['v1', 'v2', 'v3', 'v4', 'v5'])
        assert_equal([e for e in sorted(G.edges(data=True))],
                     [('v1', 'v2', {'label': '4'}), 
                      ('v1', 'v3', {'label': '3'}), 
                      ('v2', 'v3', {'label': '2'}), 
                      ('v3', 'v4', {'label': '3'}), 
                      ('v3', 'v5', {'label': '7'}), 
                      ('v4', 'v5', {'label': '6'}), 
                      ('v5', 'v1', {'label': 'foo'})])


    def test_read_LEDA(self):
        data="""#header section	  \nLEDA.GRAPH \nstring\nint\n-1\n#nodes section\n5 \n|{v1}| \n|{v2}| \n|{v3}| \n|{v4}| \n|{v5}| \n\n#edges section\n7 \n1 2 0 |{4}| \n1 3 0 |{3}| \n2 3 0 |{2}| \n3 4 0 |{3}| \n3 5 0 |{7}| \n4 5 0 |{6}| \n5 1 0 |{foo}|"""
        G=nx.parse_leda(data)

        with tempfile.NamedTemporaryFile(delete=False) as fp:
            fp.write(data)
        try:
            Gin = nx.read_leda(fp.name)
            assert_equal(sorted(G.nodes()),sorted(Gin.nodes()))
            assert_equal(sorted(G.edges()),sorted(Gin.edges()))
        finally:
            os.unlink(fp.name)

#!/usr/bin/env python
from nose.tools import *
import networkx as nx
import io,os,tempfile

class TestLEDA(object):

    def test_parse_leda(self):
        data="""#header section	  \nLEDA.GRAPH \nstring\nint\n-1\n#nodes section\n5 \n|{v1}| \n|{v2}| \n|{v3}| \n|{v4}| \n|{v5}| \n\n#edges section\n7 \n1 2 0 |{4}| \n1 3 0 |{3}| \n2 3 0 |{2}| \n3 4 0 |{3}| \n3 5 0 |{7}| \n4 5 0 |{6}| \n5 1 0 |{foo}|"""
        G=nx.parse_leda(data)
        G=nx.parse_leda(data.split('\n'))
        assert_equal(sorted(G.nodes()),
                     ['v1', 'v2', 'v3', 'v4', 'v5'])
        assert_equal([e for e in sorted(G.edges(data=True))],
                     [('v1', 'v2', {'label': '4'}), 
                      ('v1', 'v3', {'label': '3'}), 
                      ('v2', 'v3', {'label': '2'}), 
                      ('v3', 'v4', {'label': '3'}), 
                      ('v3', 'v5', {'label': '7'}), 
                      ('v4', 'v5', {'label': '6'}), 
                      ('v5', 'v1', {'label': 'foo'})])


    def test_read_LEDA(self):
        fh = io.BytesIO()
        data="""#header section	  \nLEDA.GRAPH \nstring\nint\n-1\n#nodes section\n5 \n|{v1}| \n|{v2}| \n|{v3}| \n|{v4}| \n|{v5}| \n\n#edges section\n7 \n1 2 0 |{4}| \n1 3 0 |{3}| \n2 3 0 |{2}| \n3 4 0 |{3}| \n3 5 0 |{7}| \n4 5 0 |{6}| \n5 1 0 |{foo}|"""
        G=nx.parse_leda(data)
        fh.write(data.encode('UTF-8'))
        fh.seek(0)
        Gin = nx.read_leda(fh)
        assert_equal(sorted(G.nodes()),sorted(Gin.nodes()))
        assert_equal(sorted(G.edges()),sorted(Gin.edges()))

Use io.BytesIO() instead of temporary file