diff --git a/fpdfsdk/src/fpdfedit_embeddertest.cpp b/fpdfsdk/src/fpdfedit_embeddertest.cpp
index 9db948c..1cd28cf 100644
--- a/fpdfsdk/src/fpdfedit_embeddertest.cpp
+++ b/fpdfsdk/src/fpdfedit_embeddertest.cpp
@@ -5,14 +5,55 @@
 #include "public/fpdf_edit.h"
 #include "public/fpdfview.h"
 #include "testing/embedder_test.h"
+#include "testing/gmock/include/gmock/gmock-matchers.h"
 #include "testing/gtest/include/gtest/gtest.h"
+#include "testing/test_support.h"
 
-class FPDFEditEmbeddertest : public EmbedderTest {};
+class FPDFEditEmbeddertest : public EmbedderTest, public TestSaver {};
 
 TEST_F(FPDFEditEmbeddertest, EmptyCreation) {
   EXPECT_TRUE(CreateEmptyDocument());
   FPDF_PAGE page = FPDFPage_New(document(), 1, 640.0, 480.0);
   EXPECT_NE(nullptr, page);
   EXPECT_TRUE(FPDFPage_GenerateContent(page));
+  EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
+  EXPECT_THAT(GetString(),
+              testing::MatchesRegex(
+                  "%PDF-1.7\r\n"
+                  "%\xA1\xB3\xC5\xD7\r\n"
+                  "1 0 obj\r\n"
+                  "<</Type/Catalog/Pages 2 0 R >>\r\n"
+                  "endobj\r\n"
+                  "2 0 obj\r\n"
+                  "<</Type/Pages/Count 1/Kids\\[ 4 0 R \\]>>\r\n"
+                  "endobj\r\n"
+                  "3 0 obj\r\n"
+                  "<</CreationDate\\(D:.*\\)/Creator\\(PDFium\\)>>\r\n"
+                  "endobj\r\n"
+                  "4 0 obj\r\n"
+                  "<</Type/Page/Parent 2 0 R /MediaBox\\[ 0 0 640 "
+                  "480\\]/Rotate 0/Resources<<>>/Contents 5 0 R >>\r\n"
+                  "endobj\r\n"
+                  "5 0 obj\r\n"
+                  "<</Length 8/Filter/FlateDecode>>stream\r\n"
+                  "x\x9C\x3\0\0\0\0\x1\r\n"
+                  "endstream\r\n"
+                  "endobj\r\n"
+                  "xref\r\n"
+                  "0 6\r\n"
+                  "0000000000 65535 f\r\n"
+                  "0000000017 00000 n\r\n"
+                  "0000000066 00000 n\r\n"
+                  "0000000122 00000 n\r\n"
+                  "0000000192 00000 n\r\n"
+                  "0000000301 00000 n\r\n"
+                  "trailer\r\n"
+                  "<<\r\n"
+                  "/Root 1 0 R\r\n"
+                  "/Info 3 0 R\r\n"
+                  "/Size 6/ID\\[<.*><.*>\\]>>\r\n"
+                  "startxref\r\n"
+                  "379\r\n"
+                  "%%EOF\r\n"));
   FPDFPage_Delete(document(), 1);
 }
diff --git a/fpdfsdk/src/fpdfsave_embeddertest.cpp b/fpdfsdk/src/fpdfsave_embeddertest.cpp
index bee452b..1c93f4f 100644
--- a/fpdfsdk/src/fpdfsave_embeddertest.cpp
+++ b/fpdfsdk/src/fpdfsave_embeddertest.cpp
@@ -9,64 +9,44 @@
 #include "public/fpdfview.h"
 #include "testing/embedder_test.h"
 #include "testing/fx_string_testhelpers.h"
+#include "testing/gmock/include/gmock/gmock-matchers.h"
 #include "testing/gtest/include/gtest/gtest.h"
+#include "testing/test_support.h"
 
-class FPDFSaveEmbedderTest : public EmbedderTest, public FPDF_FILEWRITE {
- public:
-  FPDFSaveEmbedderTest() {
-    FPDF_FILEWRITE::version = 1;
-    FPDF_FILEWRITE::WriteBlock = WriteBlockCallback;
-  }
-  bool SaveDocumentToString() {
-    m_String.clear();
-    return FPDF_SaveAsCopy(document(), this, 0);
-  }
-  bool SaveDocumentWithVersionToString(int version) {
-    m_String.clear();
-    return FPDF_SaveWithVersion(document(), this, 0, version);
-  }
-  const std::string& GetString() const { return m_String; }
-
- private:
-  static int WriteBlockCallback(FPDF_FILEWRITE* pFileWrite,
-                                const void* data,
-                                unsigned long size) {
-    FPDFSaveEmbedderTest* pThis =
-        static_cast<FPDFSaveEmbedderTest*>(pFileWrite);
-    pThis->m_String.append(static_cast<const char*>(data), size);
-    return 1;
-  }
-
-  std::string m_String;
-};
+class FPDFSaveEmbedderTest : public EmbedderTest, public TestSaver {};
 
 TEST_F(FPDFSaveEmbedderTest, SaveSimpleDoc) {
   EXPECT_TRUE(OpenDocument("hello_world.pdf"));
-  EXPECT_TRUE(SaveDocumentToString());
-  EXPECT_EQ("%PDF-1.7\r\n", GetString().substr(0, 10));
+  EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
+  EXPECT_THAT(GetString(), testing::StartsWith("%PDF-1.7\r\n"));
   EXPECT_EQ(843, GetString().length());
 }
 
 TEST_F(FPDFSaveEmbedderTest, SaveSimpleDocWithVersion) {
   EXPECT_TRUE(OpenDocument("hello_world.pdf"));
-  EXPECT_TRUE(SaveDocumentWithVersionToString(14));
-  EXPECT_EQ("%PDF-1.4\r\n", GetString().substr(0, 10));
+  EXPECT_TRUE(FPDF_SaveWithVersion(document(), this, 0, 14));
+  EXPECT_THAT(GetString(), testing::StartsWith("%PDF-1.4\r\n"));
   EXPECT_EQ(843, GetString().length());
 }
 
 TEST_F(FPDFSaveEmbedderTest, SaveSimpleDocWithBadVersion) {
   EXPECT_TRUE(OpenDocument("hello_world.pdf"));
-  EXPECT_TRUE(SaveDocumentWithVersionToString(-1));
-  EXPECT_EQ("%PDF-1.7\r\n", GetString().substr(0, 10));
-  EXPECT_TRUE(SaveDocumentWithVersionToString(0));
-  EXPECT_EQ("%PDF-1.7\r\n", GetString().substr(0, 10));
-  EXPECT_TRUE(SaveDocumentWithVersionToString(18));
-  EXPECT_EQ("%PDF-1.7\r\n", GetString().substr(0, 10));
+  EXPECT_TRUE(FPDF_SaveWithVersion(document(), this, 0, -1));
+  EXPECT_THAT(GetString(), testing::StartsWith("%PDF-1.7\r\n"));
+
+  ClearString();
+  EXPECT_TRUE(FPDF_SaveWithVersion(document(), this, 0, 0));
+  EXPECT_THAT(GetString(), testing::StartsWith("%PDF-1.7\r\n"));
+
+  ClearString();
+  EXPECT_TRUE(FPDF_SaveWithVersion(document(), this, 0, 18));
+  EXPECT_THAT(GetString(), testing::StartsWith("%PDF-1.7\r\n"));
 }
 
 TEST_F(FPDFSaveEmbedderTest, BUG_342) {
   EXPECT_TRUE(OpenDocument("hello_world.pdf"));
-  EXPECT_TRUE(SaveDocumentToString());
-  EXPECT_EQ(std::string::npos, GetString().find("0000000000 65536 f\r\n"));
-  EXPECT_NE(std::string::npos, GetString().find("0000000000 65535 f\r\n"));
+  EXPECT_TRUE(FPDF_SaveAsCopy(document(), this, 0));
+  EXPECT_THAT(GetString(), testing::HasSubstr("0000000000 65535 f\r\n"));
+  EXPECT_THAT(GetString(),
+              testing::Not(testing::HasSubstr("0000000000 65536 f\r\n")));
 }
diff --git a/testing/test_support.cpp b/testing/test_support.cpp
index 96e01c5..da5ea7e 100644
--- a/testing/test_support.cpp
+++ b/testing/test_support.cpp
@@ -172,3 +172,21 @@
   memcpy(pBuf, pLoader->m_pBuf + pos, size);
   return 1;
 }
+
+TestSaver::TestSaver() {
+  FPDF_FILEWRITE::version = 1;
+  FPDF_FILEWRITE::WriteBlock = WriteBlockCallback;
+}
+
+void TestSaver::ClearString() {
+  m_String.clear();
+}
+
+// static
+int TestSaver::WriteBlockCallback(FPDF_FILEWRITE* pFileWrite,
+                                  const void* data,
+                                  unsigned long size) {
+  TestSaver* pThis = static_cast<TestSaver*>(pFileWrite);
+  pThis->m_String.append(static_cast<const char*>(data), size);
+  return 1;
+}
diff --git a/testing/test_support.h b/testing/test_support.h
index 9457041..f59d544 100644
--- a/testing/test_support.h
+++ b/testing/test_support.h
@@ -10,6 +10,7 @@
 #include <string>
 
 #include "public/fpdfview.h"
+#include "public/fpdf_save.h"
 
 #ifdef PDF_ENABLE_V8
 #include "v8/include/v8.h"
@@ -62,4 +63,19 @@
   const size_t m_Len;
 };
 
+class TestSaver : public FPDF_FILEWRITE {
+ public:
+  TestSaver();
+
+  void ClearString();
+  const std::string& GetString() const { return m_String; }
+
+ private:
+  static int WriteBlockCallback(FPDF_FILEWRITE* pFileWrite,
+                                const void* data,
+                                unsigned long size);
+
+  std::string m_String;
+};
+
 #endif  // TESTING_EMBEDDER_TEST_SUPPORT_H_