Ekdohibs/zig
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Merge pull request #4091 from xackus/json_copy_strings

Browse Source 
json: implement copy_strings=false
This commit is contained in:
Andrew Kelley 2020-01-07 16:42:14 -05:00 committed by GitHub
commit 9f064bcf74
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 51 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

63
lib/std/json.zig
View File

@ -1414,11 +1414,9 @@ pub const Parser = struct {
}
fn parseString(p: *Parser, allocator: *Allocator, s: std.meta.TagPayloadType(Token, Token.String), input: []const u8, i: usize) !Value {
// TODO: We don't strictly have to copy values which do not contain any escape
// characters if flagged with the option.
const slice = s.slice(input, i);
switch (s.escapes) {
.None => return Value{ .String = try mem.dupe(allocator, u8, slice) },
.None => return Value{ .String = if (p.copy_strings) try mem.dupe(allocator, u8, slice) else slice },
.Some => |some_escapes| {
const output = try allocator.alloc(u8, s.decodedLength());
errdefer allocator.free(output);
@ -1497,7 +1495,10 @@ fn unescapeString(output: []u8, input: []const u8) !void {
}
test "json.parser.dynamic" {
var p = Parser.init(debug.global_allocator, false);
var memory: [1024 * 16]u8 = undefined;
var buf_alloc = std.heap.FixedBufferAllocator.init(&memory);
var p = Parser.init(&buf_alloc.allocator, false);
defer p.deinit();
const s =
@ -1600,17 +1601,21 @@ test "write json then parse it" {
testing.expect(mem.eql(u8, tree.root.Object.get("str").?.value.String, "hello"));
}
fn test_parse(json_str: []const u8) !Value {
var p = Parser.init(debug.global_allocator, false);
fn test_parse(memory: []u8, json_str: []const u8) !Value {
// buf_alloc goes out of scope, but we don't use it after parsing
var buf_alloc = std.heap.FixedBufferAllocator.init(memory);
var p = Parser.init(&buf_alloc.allocator, false);
return (try p.parse(json_str)).root;
}
test "parsing empty string gives appropriate error" {
testing.expectError(error.UnexpectedEndOfJson, test_parse(""));
var memory: [1024 * 4]u8 = undefined;
testing.expectError(error.UnexpectedEndOfJson, test_parse(&memory, ""));
}
test "integer after float has proper type" {
const json = try test_parse(
var memory: [1024 * 8]u8 = undefined;
const json = try test_parse(&memory,
\\{
\\ "float": 3.14,
\\ "ints": [1, 2, 3]
@ -1620,6 +1625,7 @@ test "integer after float has proper type" {
}
test "escaped characters" {
var memory: [1024 * 16]u8 = undefined;
const input =
\\{
\\ "backslash": "\\",
@ -1635,10 +1641,7 @@ test "escaped characters" {
\\}
;
var p = Parser.init(debug.global_allocator, false);
const tree = try p.parse(input);
const obj = tree.root.Object;
const obj = (try test_parse(&memory, input)).Object;
testing.expectEqualSlices(u8, obj.get("backslash").?.value.String, "\\");
testing.expectEqualSlices(u8, obj.get("forwardslash").?.value.String, "/");
@ -1651,3 +1654,39 @@ test "escaped characters" {
testing.expectEqualSlices(u8, obj.get("unicode").?.value.String, "ą");
testing.expectEqualSlices(u8, obj.get("surrogatepair").?.value.String, "😂");
}
test "string copy option" {
const input =
\\{
\\ "noescape": "aą😂",
\\ "simple": "\\\/\n\r\t\f\b\"",
\\ "unicode": "\u0105",
\\ "surrogatepair": "\ud83d\ude02"
\\}
;
var mem_buffer: [1024 * 16]u8 = undefined;
var buf_alloc = std.heap.FixedBufferAllocator.init(&mem_buffer);
const tree_nocopy = try Parser.init(&buf_alloc.allocator, false).parse(input);
const obj_nocopy = tree_nocopy.root.Object;
const tree_copy = try Parser.init(&buf_alloc.allocator, true).parse(input);
const obj_copy = tree_copy.root.Object;
for ([_][]const u8{ "noescape", "simple", "unicode", "surrogatepair" }) |field_name| {
testing.expectEqualSlices(u8, obj_nocopy.getValue(field_name).?.String, obj_copy.getValue(field_name).?.String);
}
const nocopy_addr = &obj_nocopy.getValue("noescape").?.String[0];
const copy_addr = &obj_copy.getValue("noescape").?.String[0];
var found_nocopy = false;
for (input) |_, index| {
testing.expect(copy_addr != &input[index]);
if (nocopy_addr == &input[index]) {
found_nocopy = true;
}
}
testing.expect(found_nocopy);
}