Ensure that UTF-8 is used to read and write snippets in operation macro

Fixes gh-696

spring-restdocs-asciidoctor-support/src/main/resources/extensions/operation_block_macro.rb

@@ -37,6 +37,7 @@ class OperationBlockMacro < Asciidoctor::Extensions::BlockMacroProcessor
 
   def do_read_snippets(snippets, parent, operation, snippet_titles)
     content = StringIO.new
+    content.set_encoding "UTF-8"
     section_id = parent.id
     snippets.each do |snippet|
       append_snippet_block(content, snippet, section_id,
@@ -93,7 +94,7 @@ class OperationBlockMacro < Asciidoctor::Extensions::BlockMacroProcessor
 
   def write_content(content, snippet, operation)
     if File.file? snippet.path
-      content.puts File.readlines(snippet.path).join
+      content.puts File.readlines(snippet.path, :encoding => 'UTF-8').join
     else
       warn "Snippet #{snippet.name} not found at #{snippet.path} for"\
            " operation #{operation}"

spring-restdocs-asciidoctor/src/test/java/org/springframework/restdocs/asciidoctor/AbstractOperationBlockMacroTests.java

@@ -19,6 +19,7 @@ package org.springframework.restdocs.asciidoctor;
 import java.io.File;
 import java.io.IOException;
 import java.net.URISyntaxException;
+import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
@@ -199,7 +200,7 @@ public abstract class AbstractOperationBlockMacroTests {
 
 	private String getExpectedContentFromFile(String fileName) throws URISyntaxException, IOException {
 		Path filePath = Paths.get(this.getClass().getResource("/operations/" + fileName + ".html").toURI());
-		String content = new String(Files.readAllBytes(filePath));
+		String content = new String(Files.readAllBytes(filePath), StandardCharsets.UTF_8);
 		if (isWindows()) {
 			return content.replace("\r\n", "\n");
 		}

spring-restdocs-asciidoctor/src/test/resources/operations/all-snippets.html

@@ -13,7 +13,7 @@
 <div class="sectionbody">
 <div class="listingblock">
 <div class="content">
-<pre class="highlight nowrap"><code class="language-http" data-lang="http">mycustomsnippet</code></pre>
+<pre class="highlight nowrap"><code class="language-http" data-lang="http">mycustomsnippet-äöü</code></pre>
 </div>
 </div>
 </div>

spring-restdocs-asciidoctor/src/test/resources/operations/custom-snippet-custom-title.html

@@ -3,7 +3,7 @@
 <div class="sectionbody">
 <div class="listingblock">
 <div class="content">
-<pre class="highlight nowrap"><code class="language-http" data-lang="http">mycustomsnippet</code></pre>
+<pre class="highlight nowrap"><code class="language-http" data-lang="http">mycustomsnippet-äöü</code></pre>
 </div>
 </div>
 </div>

spring-restdocs-asciidoctor/src/test/resources/operations/custom-snippet-default-title.html

@@ -3,7 +3,7 @@
 <div class="sectionbody">
 <div class="listingblock">
 <div class="content">
-<pre class="highlight nowrap"><code class="language-http" data-lang="http">mycustomsnippet</code></pre>
+<pre class="highlight nowrap"><code class="language-http" data-lang="http">mycustomsnippet-äöü</code></pre>
 </div>
 </div>
 </div>

spring-restdocs-asciidoctor/src/test/resources/some-operation/custom-snippet.adoc

@@ -1,4 +1,4 @@
 [source,http,options="nowrap"]
 ----
-mycustomsnippet
+mycustomsnippet-äöü
 ----