no direct reference if egg in URL

piptools/utils.py

@@ -116,6 +116,8 @@ def format_requirement(
             # file:./ is a hack to use a relative path to a package
             # Direct reference does not work for this, so only the URL is used
             line = ireq.link.url
+        elif "#" in ireq.link.url and "egg=" in ireq.link.url.rsplit("#", 1)[1]:
+            line = ireq.link.url
         else:
             line = f"{ireq.name.lower()} @ {ireq.link.url}"
     else:

tests/test_utils.py

@@ -27,36 +27,44 @@ def test_format_requirement(from_line):
     assert format_requirement(ireq) == "test==1.2"
 
 
-def test_format_requirement_url(from_line):
-    ireq = from_line("https://example.com/example.zip")
-    assert format_requirement(ireq) == "https://example.com/example.zip"
-
-
-def test_format_requirement_url_with_direct_link(from_line):
-    ireq = from_line("example @ https://example.com/example.zip")
-    assert format_requirement(ireq) == "example @ https://example.com/example.zip"
-
-
-def test_format_requirement_url_with_direct_link_is_lower_case(from_line):
-    ireq = from_line("https://example.com/example.zip#egg=Example")
-    assert ireq.name == "Example"
-    assert (
-        format_requirement(ireq)
-        == "example @ https://example.com/example.zip#egg=Example"
-    )
-
-
-def test_format_requirement_url_with_egg(from_line):
-    ireq = from_line("https://example.com/example.zip#egg=example")
-    assert (
-        format_requirement(ireq)
-        == "example @ https://example.com/example.zip#egg=example"
-    )
-
-
-def test_format_requirement_url_relative_path(from_line):
-    ireq = from_line("file:./vendor/package.zip")
-    assert format_requirement(ireq) == "file:./vendor/package.zip"
+@pytest.mark.parametrize(
+    ("line", "expected"),
+    (
+        pytest.param(
+            "https://example.com/example.zip",
+            "https://example.com/example.zip",
+            id="simple url",
+        ),
+        pytest.param(
+            "example @ https://example.com/example.zip",
+            "example @ https://example.com/example.zip",
+            id="direct reference",
+        ),
+        pytest.param(
+            "Example @ https://example.com/example.zip",
+            "example @ https://example.com/example.zip",
+            id="direct reference lower case",
+        ),
+        pytest.param(
+            "https://example.com/example.zip#egg=example",
+            "https://example.com/example.zip#egg=example",
+            id="url with egg",
+        ),
+        pytest.param(
+            "example @ https://example.com/example.zip?egg=test#subdirectory=project_a",
+            "example @ https://example.com/example.zip?egg=test#subdirectory=project_a",
+            id="egg as query",
+        ),
+        pytest.param(
+            "file:./vendor/package.zip#egg=example",
+            "file:./vendor/package.zip#egg=example",
+            id="relative path",
+        ),
+    ),
+)
+def test_format_requirement_url(from_line, line, expected):
+    ireq = from_line(line)
+    assert format_requirement(ireq) == expected
 
 
 def test_format_requirement_editable_vcs(from_editable):

tests/test_writer.py

@@ -148,7 +148,7 @@ def test_iter_lines__hash_missing(capsys, writer, from_line):
 
     expected_lines = (
         MESSAGE_UNHASHED_PACKAGE,
-        "example @ file:///example/#egg=example",
+        "file:///example/#egg=example",
         "test==1.2 \\\n    --hash=FAKEHASH",
     )
     assert tuple(lines) == expected_lines
@@ -173,8 +173,8 @@ def test_iter_lines__no_warn_if_only_unhashable_packages(writer, from_line):
     lines = writer._iter_lines(ireqs, hashes=hashes)
 
     expected_lines = (
-        "unhashable-pkg1 @ file:///unhashable-pkg1/#egg=unhashable-pkg1",
-        "unhashable-pkg2 @ file:///unhashable-pkg2/#egg=unhashable-pkg2",
+        "file:///unhashable-pkg1/#egg=unhashable-pkg1",
+        "file:///unhashable-pkg2/#egg=unhashable-pkg2",
     )
     assert tuple(lines) == expected_lines