tree-sitter/test/helpers/spy_input.cc
Max Brunsfeld 6dc0ff359d Rename spec -> test
'Test' is a lot more straightforward of a name.
2017-03-09 20:40:01 -08:00

133 lines
3.9 KiB
C++

#include "helpers/spy_input.h"
#include "helpers/encoding_helpers.h"
#include <string.h>
#include <algorithm>
#include <assert.h>
using std::pair;
using std::string;
static const size_t UTF8_MAX_CHAR_SIZE = 4;
SpyInput::SpyInput(string content, size_t chars_per_chunk) :
chars_per_chunk(chars_per_chunk),
buffer_size(UTF8_MAX_CHAR_SIZE * chars_per_chunk),
buffer(new char[buffer_size]),
byte_offset(0),
content(content),
encoding(TSInputEncodingUTF8),
strings_read({""}) {}
SpyInput::~SpyInput() {
delete[] buffer;
}
const char * SpyInput::read(void *payload, uint32_t *bytes_read) {
auto spy = static_cast<SpyInput *>(payload);
if (spy->byte_offset > spy->content.size()) {
*bytes_read = 0;
return "";
}
long byte_count = string_byte_for_character(spy->encoding, spy->content, spy->byte_offset, spy->chars_per_chunk);
if (byte_count < 0)
byte_count = spy->content.size() - spy->byte_offset;
string result = spy->content.substr(spy->byte_offset, byte_count);
*bytes_read = byte_count;
spy->strings_read.back() += result;
spy->byte_offset += byte_count;
/*
* This class stores its entire `content` in a contiguous buffer, but we want
* to ensure that the code under test cannot accidentally read more than
* `*bytes_read` bytes past the returned pointer. To make sure that this type
* of error does not fly, we copy the chunk into a zeroed-out buffer and
* return a reference to that buffer, rather than a pointer into the main
* content.
*/
memset(spy->buffer, 0, spy->buffer_size);
memcpy(spy->buffer, result.data(), byte_count);
return spy->buffer;
}
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;
}
TSInput SpyInput::input() {
TSInput result;
result.payload = this;
result.encoding = encoding;
result.seek = seek;
result.read = read;
return result;
}
static TSPoint get_extent(string text) {
TSPoint result = {0, 0};
for (auto i = text.begin(); i != text.end(); i++) {
if (*i == '\n') {
result.row++;
result.column = 0;
} else {
result.column++;
}
}
return result;
}
TSInputEdit SpyInput::replace(size_t start_byte, size_t bytes_removed, string text) {
auto swap = swap_substr(start_byte, bytes_removed, text);
size_t bytes_added = text.size();
undo_stack.push_back(SpyInputEdit{start_byte, bytes_added, swap.first});
TSInputEdit result = {};
result.start_byte = start_byte;
result.bytes_added = bytes_added;
result.bytes_removed = bytes_removed;
result.start_point = swap.second;
result.extent_removed = get_extent(swap.first);
result.extent_added = get_extent(text);
return result;
}
TSInputEdit SpyInput::undo() {
SpyInputEdit entry = undo_stack.back();
undo_stack.pop_back();
auto swap = swap_substr(entry.start_byte, entry.bytes_removed, entry.text_inserted);
TSInputEdit result;
result.start_byte = entry.start_byte;
result.bytes_removed = entry.bytes_removed;
result.bytes_added = entry.text_inserted.size();
result.start_point = swap.second;
result.extent_removed = get_extent(swap.first);
result.extent_added = get_extent(entry.text_inserted);
return result;
}
pair<string, TSPoint> SpyInput::swap_substr(size_t start_byte, size_t bytes_removed, string text) {
TSPoint start_position = {0, 0};
for (auto i = content.begin(), n = content.begin() + start_byte; i < n; i++) {
if (*i == '\n') {
start_position.row++;
start_position.column = 0;
} else {
start_position.column++;
}
}
string text_removed = content.substr(start_byte, bytes_removed);
content.erase(start_byte, bytes_removed);
content.insert(start_byte, text);
return {text_removed, start_position};
}
void SpyInput::clear() {
strings_read.clear();
}