diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/std/json.zig | 31 |
1 files changed, 25 insertions, 6 deletions
diff --git a/lib/std/json.zig b/lib/std/json.zig index 5b4203501b..ed90efb791 100644 --- a/lib/std/json.zig +++ b/lib/std/json.zig @@ -1464,6 +1464,8 @@ pub const ParseOptions = struct { /// If false, finding an unknown field returns an error. ignore_unknown_fields: bool = false, + + allow_trailing_data: bool = false, }; fn skipValue(tokens: *TokenStream) !void { @@ -1627,6 +1629,8 @@ fn parseInternal(comptime T: type, token: Token, tokens: *TokenStream, options: .ObjectEnd => break, .String => |stringToken| { const key_source_slice = stringToken.slice(tokens.slice, tokens.i - 1); + var child_options = options; + child_options.allow_trailing_data = true; var found = false; inline for (structInfo.fields) |field, i| { // TODO: using switches here segfault the compiler (#2727?) @@ -1643,24 +1647,24 @@ fn parseInternal(comptime T: type, token: Token, tokens: *TokenStream, options: // } if (options.duplicate_field_behavior == .UseFirst) { // unconditonally ignore value. for comptime fields, this skips check against default_value - parseFree(field.field_type, try parse(field.field_type, tokens, options), options); + parseFree(field.field_type, try parse(field.field_type, tokens, child_options), child_options); found = true; break; } else if (options.duplicate_field_behavior == .Error) { return error.DuplicateJSONField; } else if (options.duplicate_field_behavior == .UseLast) { if (!field.is_comptime) { - parseFree(field.field_type, @field(r, field.name), options); + parseFree(field.field_type, @field(r, field.name), child_options); } fields_seen[i] = false; } } if (field.is_comptime) { - if (!try parsesTo(field.field_type, field.default_value.?, tokens, options)) { + if (!try parsesTo(field.field_type, field.default_value.?, tokens, child_options)) { return error.UnexpectedValue; } } else { - @field(r, field.name) = try parse(field.field_type, tokens, options); + @field(r, field.name) = try parse(field.field_type, tokens, child_options); } fields_seen[i] = true; found = true; @@ -1697,6 +1701,8 @@ fn parseInternal(comptime T: type, token: Token, tokens: *TokenStream, options: .ArrayBegin => { var r: T = undefined; var i: usize = 0; + var child_options = options; + child_options.allow_trailing_data = true; errdefer { // Without the r.len check `r[i]` is not allowed if (r.len > 0) while (true) : (i -= 1) { @@ -1705,7 +1711,7 @@ fn parseInternal(comptime T: type, token: Token, tokens: *TokenStream, options: }; } while (i < r.len) : (i += 1) { - r[i] = try parse(arrayInfo.child, tokens, options); + r[i] = try parse(arrayInfo.child, tokens, child_options); } const tok = (try tokens.next()) orelse return error.UnexpectedEndOfJson; switch (tok) { @@ -1786,7 +1792,13 @@ fn parseInternal(comptime T: type, token: Token, tokens: *TokenStream, options: pub fn parse(comptime T: type, tokens: *TokenStream, options: ParseOptions) !T { const token = (try tokens.next()) orelse return error.UnexpectedEndOfJson; - return parseInternal(T, token, tokens, options); + const r = try parseInternal(T, token, tokens, options); + errdefer parseFree(T, r, options); + if (!options.allow_trailing_data) { + if ((try tokens.next()) != null) unreachable; + assert(tokens.i >= tokens.slice.len); + } + return r; } /// Releases resources created by `parse`. @@ -1871,6 +1883,13 @@ test "parse into enum" { try testing.expectError(error.InvalidEnumTag, parse(T, &TokenStream.init("\"Qux\""), ParseOptions{})); } +test "parse with trailing data" { + try testing.expectEqual(false, try parse(bool, &TokenStream.init("falsed"), ParseOptions{ .allow_trailing_data = true })); + try testing.expectError(error.InvalidTopLevelTrailing, parse(bool, &TokenStream.init("falsed"), ParseOptions{ .allow_trailing_data = false })); + // trailing whitespace is okay + try testing.expectEqual(false, try parse(bool, &TokenStream.init("false \n"), ParseOptions{ .allow_trailing_data = false })); +} + test "parse into that allocates a slice" { try testing.expectError(error.AllocatorRequired, parse([]u8, &TokenStream.init("\"foo\""), ParseOptions{})); |