Prettier was assuming files were always 50+ characters long (#699)

Author: nedtwigg

CHANGES.md

@@ -10,6 +10,8 @@ This document is intended for Spotless developers.
 We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (starting after version `1.27.0`).
 
 ## [Unreleased]
+### Fixed
+* Don't assume that file content passed into Prettier is at least 50 characters (https://github.com/diffplug/spotless/pull/699).
 
 ## [2.6.1] - 2020-09-12
 ### Fixed

lib/src/main/java/com/diffplug/spotless/npm/PrettierFormatterStep.java

@@ -113,7 +113,7 @@ public PrettierFilePathPassingFormatterFunc(String prettierConfigOptions, Pretti
 
 		@Override
 		public String applyWithFile(String unix, File file) throws Exception {
-			FormattedPrinter.SYSOUT.print("formatting String '" + unix.substring(0, 50) + "[...]' in file '" + file + "'");
+			FormattedPrinter.SYSOUT.print("formatting String '" + unix.substring(0, Math.min(50, unix.length() - 1)) + "[...]' in file '" + file + "'");
 
 			final String prettierConfigOptionsWithFilepath = assertFilepathInConfigOptions(file);
 			return restService.format(unix, prettierConfigOptionsWithFilepath);

plugin-gradle/CHANGES.md

@@ -3,6 +3,8 @@
 We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (starting after version `3.27.0`).
 
 ## [Unreleased]
+### Fixed
+* Don't assume that file content passed into Prettier is at least 50 characters (https://github.com/diffplug/spotless/pull/699).
 
 ## [5.5.1] - 2020-09-12
 ### Fixed

plugin-maven/CHANGES.md

@@ -3,6 +3,8 @@
 We adhere to the [keepachangelog](https://keepachangelog.com/en/1.0.0/) format (starting after version `1.27.0`).
 
 ## [Unreleased]
+### Fixed
+* Don't assume that file content passed into Prettier is at least 50 characters (https://github.com/diffplug/spotless/pull/699).
 
 ## [2.4.0] - 2020-09-17
 ### Added