From a15e9741504d8c8cae3e2b73e3e07287e72e4362 Mon Sep 17 00:00:00 2001
From: Max Brunsfeld <maxbrunsfeld@gmail.com>
Date: Tue, 21 Mar 2017 12:14:04 -0700
Subject: [PATCH] Make clearer assertions about SpyInput's read strings

---
 test/helpers/spy_input.cc     | 30 +++++++++++++++++++++++++-----
 test/helpers/spy_input.h      |  3 ++-
 test/runtime/document_test.cc |  4 ++--
 test/runtime/parser_test.cc   |  4 ++--
 4 files changed, 31 insertions(+), 10 deletions(-)

diff --git a/test/helpers/spy_input.cc b/test/helpers/spy_input.cc
index 6c479c16..bdcb2709 100644
--- a/test/helpers/spy_input.cc
+++ b/test/helpers/spy_input.cc
@@ -6,6 +6,7 @@
 
 using std::pair;
 using std::string;
+using std::vector;
 
 static const size_t UTF8_MAX_CHAR_SIZE = 4;
 
@@ -16,12 +17,25 @@ SpyInput::SpyInput(string content, size_t chars_per_chunk) :
   byte_offset(0),
   content(content),
   encoding(TSInputEncodingUTF8),
-  strings_read({""}) {}
+  ranges_read({}) {}
 
 SpyInput::~SpyInput() {
   delete[] buffer;
 }
 
+static void add_byte_range(vector<pair<uint32_t, uint32_t>> *ranges,
+                           uint32_t start, uint32_t count) {
+  uint32_t end = start + count;
+  for (auto &range : *ranges) {
+    if (range.first <= start && start <= range.second) {
+      if (start < range.first) range.first = start;
+      if (end > range.second) range.second = end;
+      return;
+    }
+  }
+  ranges->push_back({start, end});
+}
+
 const char * SpyInput::read(void *payload, uint32_t *bytes_read) {
   auto spy = static_cast<SpyInput *>(payload);
 
@@ -36,7 +50,7 @@ const char * SpyInput::read(void *payload, uint32_t *bytes_read) {
 
   string result = spy->content.substr(spy->byte_offset, byte_count);
   *bytes_read = byte_count;
-  spy->strings_read.back() += result;
+  add_byte_range(&spy->ranges_read, spy->byte_offset, byte_count);
   spy->byte_offset += byte_count;
 
   /*
@@ -54,12 +68,18 @@ const char * SpyInput::read(void *payload, uint32_t *bytes_read) {
 
 int SpyInput::seek(void *payload, uint32_t character, uint32_t byte) {
   auto spy = static_cast<SpyInput *>(payload);
-  if (spy->strings_read.size() == 0 || spy->strings_read.back().size() > 0)
-    spy->strings_read.push_back("");
   spy->byte_offset = byte;
   return 0;
 }
 
+vector<string> SpyInput::strings_read() const {
+  vector<string> result;
+  for (auto &range : ranges_read) {
+    result.push_back(content.substr(range.first, range.second - range.first));
+  }
+  return result;
+}
+
 TSInput SpyInput::input() {
   TSInput result;
   result.payload = this;
@@ -129,5 +149,5 @@ pair<string, TSPoint> SpyInput::swap_substr(size_t start_byte, size_t bytes_remo
 }
 
 void SpyInput::clear() {
-  strings_read.clear();
+  ranges_read.clear();
 }
diff --git a/test/helpers/spy_input.h b/test/helpers/spy_input.h
index a81213eb..9e0ee8d1 100644
--- a/test/helpers/spy_input.h
+++ b/test/helpers/spy_input.h
@@ -30,10 +30,11 @@ class SpyInput {
   void clear();
   TSInputEdit replace(size_t start_char, size_t chars_removed, std::string text);
   TSInputEdit undo();
+  std::vector<std::string> strings_read() const;
 
   std::string content;
   TSInputEncoding encoding;
-  std::vector<std::string> strings_read;
+  std::vector<std::pair<uint32_t, uint32_t>> ranges_read;
 };
 
 #endif  // HELPERS_SPY_INPUT_H_
diff --git a/test/runtime/document_test.cc b/test/runtime/document_test.cc
index 71d7b8c7..d732fbc8 100644
--- a/test/runtime/document_test.cc
+++ b/test/runtime/document_test.cc
@@ -94,7 +94,7 @@ describe("Document", [&]() {
       ts_document_set_input(document, spy_input->input());
       AssertThat(ts_document_root_node(document), Equals<TSNode>(root));
       AssertThat(ts_node_has_changes(root), IsFalse());
-      AssertThat(spy_input->strings_read, Equals(vector<string>({ "" })));
+      AssertThat(spy_input->strings_read(), IsEmpty());
     });
 
     it("reads text from the new input for future parses", [&]() {
@@ -113,7 +113,7 @@ describe("Document", [&]() {
       assert_node_string_equals(
         new_root,
         "(object (pair (string) (array (null) (number))))");
-      AssertThat(spy_input->strings_read, Equals(vector<string>({" [null, 2" })));
+      AssertThat(spy_input->strings_read(), Equals(vector<string>({" [null, 2" })));
     });
 
     it("allows setting input string with length", [&]() {
diff --git a/test/runtime/parser_test.cc b/test/runtime/parser_test.cc
index 0a075aba..d9aee54a 100644
--- a/test/runtime/parser_test.cc
+++ b/test/runtime/parser_test.cc
@@ -254,7 +254,7 @@ describe("Parser", [&]() {
             "(identifier) "
             "(math_op (number) (member_access (identifier) (identifier))))))");
 
-        AssertThat(input->strings_read, Equals(vector<string>({ " + abc.d)" })));
+        AssertThat(input->strings_read(), Equals(vector<string>({ " abc.d);" })));
       });
     });
 
@@ -279,7 +279,7 @@ describe("Parser", [&]() {
               "(number) "
               "(math_op (number) (math_op (number) (identifier)))))))");
 
-        AssertThat(input->strings_read, Equals(vector<string>({ "123 || 5 +" })));
+        AssertThat(input->strings_read(), Equals(vector<string>({"123 || 5 ", ";"})));
       });
     });