Merge ffb510c56a into 9c66bafa52

tests/test_export.py

@@ -0,0 +1,101 @@
+import csv
+import io
+import sqlite3
+
+import pytest
+
+from sqlite_utils.export import rows_to_csv_file
+
+
+def _cursor():
+    db = sqlite3.connect(":memory:")
+    db.execute("create table creatures (id integer, name text)")
+    db.executemany(
+        "insert into creatures (id, name) values (?, ?)",
+        ((1, "Cleo"), (2, "Cardi, Jr.")),
+    )
+    return db, db.execute("select id, name from creatures order by id")
+
+
+def test_rows_to_csv_file():
+    db, cursor = _cursor()
+    output = io.StringIO(newline="")
+    rows_to_csv_file(cursor, output, lineterminator="\n")
+    assert output.getvalue() == 'id,name\n1,Cleo\n2,"Cardi, Jr."\n'
+    db.close()
+
+
+def test_rows_to_csv_file_without_header():
+    db, cursor = _cursor()
+    output = io.StringIO(newline="")
+    rows_to_csv_file(cursor, output, header=False, lineterminator="\n")
+    assert output.getvalue() == '1,Cleo\n2,"Cardi, Jr."\n'
+    db.close()
+
+
+def test_rows_to_csv_file_tsv():
+    db, cursor = _cursor()
+    output = io.StringIO(newline="")
+    rows_to_csv_file(cursor, output, dialect="excel-tab", lineterminator="\n")
+    assert output.getvalue() == "id\tname\n1\tCleo\n2\tCardi, Jr.\n"
+    db.close()
+
+
+def test_rows_to_csv_file_accepts_dialect_class():
+    class PipeDialect(csv.excel):
+        delimiter = "|"
+
+    db, cursor = _cursor()
+    output = io.StringIO(newline="")
+    rows_to_csv_file(cursor, output, dialect=PipeDialect, lineterminator="\n")
+    assert output.getvalue() == "id|name\n1|Cleo\n2|Cardi, Jr.\n"
+    db.close()
+
+
+def test_rows_to_csv_file_with_mapping_row_factory():
+    db = sqlite3.connect(":memory:")
+    db.execute("create table creatures (id integer, name text)")
+    db.executemany(
+        "insert into creatures (id, name) values (?, ?)",
+        ((1, "Cleo"), (2, "Cardi, Jr.")),
+    )
+
+    def dict_factory(cursor, row):
+        return {column[0]: value for column, value in zip(cursor.description, row)}
+
+    db.row_factory = dict_factory
+    cursor = db.execute("select id, name from creatures order by id")
+    output = io.StringIO(newline="")
+    rows_to_csv_file(cursor, output, lineterminator="\n")
+    assert output.getvalue() == 'id,name\n1,Cleo\n2,"Cardi, Jr."\n'
+    db.close()
+
+
+def test_rows_to_csv_file_rejects_duplicate_mapping_columns():
+    db = sqlite3.connect(":memory:")
+    db.execute("create table creatures (id integer, name text)")
+    db.execute("insert into creatures (id, name) values (1, 'Cleo')")
+
+    def dict_factory(cursor, row):
+        return {column[0]: value for column, value in zip(cursor.description, row)}
+
+    db.row_factory = dict_factory
+    cursor = db.execute("select id as value, name as value from creatures")
+    output = io.StringIO(newline="")
+    with pytest.raises(
+        ValueError, match="Mapping rows cannot represent duplicate column names"
+    ):
+        rows_to_csv_file(cursor, output, lineterminator="\n")
+    assert output.getvalue() == ""
+    db.close()
+
+
+@pytest.mark.parametrize("header", (True, False))
+def test_rows_to_csv_file_requires_result_columns(header):
+    db = sqlite3.connect(":memory:")
+    cursor = db.execute("create table creatures (id integer)")
+    output = io.StringIO(newline="")
+    with pytest.raises(ValueError, match="Cursor does not have result columns"):
+        rows_to_csv_file(cursor, output, header=header)
+    assert output.getvalue() == ""
+    db.close()