Omit extra newline when printing to stdout

CHANGELOG.md

@@ -4,6 +4,11 @@ All notable changes to this project will be documented in this file.
 
 ## [Unreleased]
 
+### Formatting Changes and Bug Fixes
+
+- sqlfmt no longer includes an extra trailing newline when writing formatted code to stdout.
+  ([#729](https://github.com/tconbeer/sqlfmt/issues/729), [#730](https://github.com/tconbeer/sqlfmt/pull/730))
+
 ## [0.28.2] - 2025-10-24
 
 ### Formatting Changes and Bug Fixes

src/sqlfmt/report.py

@@ -31,11 +31,11 @@ def unstyle_output(msg: str) -> str:
     return s
 
 
-def display_output(msg: str, err: bool = True) -> None:
+def display_output(msg: str, err: bool = True, nl: bool = True) -> None:
     """
-    A thin wrapper around click.echo; defaults to printing to stderr.
+    A thin wrapper around click.echo; defaults to stderr with trailing newline.
     """
-    click.echo(msg, err=err)
+    click.echo(msg, err=err, nl=nl)
 
 
 @dataclass
@@ -61,9 +61,10 @@ def __post_init__(self) -> None:
     def maybe_print_to_stdout(self) -> None:
         """
         If sqlfmt received a query via stdin, print the formatted string to stdout
+        without an additional trailing newline
         """
         if self.source_path == STDIN_PATH:
-            display_output(self.formatted_string, err=False)
+            display_output(self.formatted_string, err=False, nl=False)
 
     @property
     def has_changed(self) -> bool:

tests/functional_tests/test_end_to_end.py

@@ -120,8 +120,8 @@ def test_end_to_end_errors(
 @pytest.mark.parametrize(
     "options,stream_input,expected_stdout,expected_exit",
     [
-        ("-", "select    1\n", "select 1\n\n", 0),
-        ("-", "select 1\n", "select 1\n\n", 0),
+        ("-", "select    1\n", "select 1\n", 0),  # removes excess space
+        ("-", "select 1\n\n", "select 1\n", 0),  # one trailing newline
         ("- --check", "select    1\n", "", 1),
         ("- --diff", "select    1\n", "", 1),
         ("- --check", "select 1\n", "", 0),

tests/unit_tests/test_cli.py

@@ -72,7 +72,7 @@ def test_stdin(sqlfmt_runner: CliRunner) -> None:
     stream_input = "select 1"
     results = sqlfmt_runner.invoke(sqlfmt_main, args="-", input=stream_input)
     assert results.exit_code == 0
-    assert results.stdout == "select 1\n\n"
+    assert results.stdout == "select 1\n"
 
 
 def test_preformatted_check(sqlfmt_runner: CliRunner, preformatted_dir: Path) -> None: