Merge pull request #4543 from daurnimator/cleanup-json

std.json improvements

1 files changed, 27 insertions, 59 deletions

diff --git a/lib/std/json/write_stream.zig b/lib/std/json/write_stream.zig
index cbe556dcfc..60974a207e 100644
--- a/lib/std/json/write_stream.zig
+++ b/lib/std/json/write_stream.zig
@@ -21,14 +21,10 @@ pub fn WriteStream(comptime OutStream: type, comptime max_depth: usize) type {
 
         pub const Stream = OutStream;
 
-        /// The string used for indenting.
-        one_indent: []const u8 = " ",
-
-        /// The string used as a newline character.
-        newline: []const u8 = "\n",
-
-        /// The string used as spacing.
-        space: []const u8 = " ",
+        whitespace: std.json.StringifyOptions.Whitespace = std.json.StringifyOptions.Whitespace{
+            .indent_level = 0,
+            .indent = .{ .Space = 1 },
+        },
 
         stream: OutStream,
         state_index: usize,
@@ -49,12 +45,14 @@ pub fn WriteStream(comptime OutStream: type, comptime max_depth: usize) type {
             assert(self.state[self.state_index] == State.Value); // need to call arrayElem or objectField
             try self.stream.writeByte('[');
             self.state[self.state_index] = State.ArrayStart;
+            self.whitespace.indent_level += 1;
         }
 
         pub fn beginObject(self: *Self) !void {
             assert(self.state[self.state_index] == State.Value); // need to call arrayElem or objectField
             try self.stream.writeByte('{');
             self.state[self.state_index] = State.ObjectStart;
+            self.whitespace.indent_level += 1;
         }
 
         pub fn arrayElem(self: *Self) !void {
@@ -90,8 +88,10 @@ pub fn WriteStream(comptime OutStream: type, comptime max_depth: usize) type {
                     self.pushState(.Value);
                     try self.indent();
                     try self.writeEscapedString(name);
-                    try self.stream.writeAll(":");
-                    try self.stream.writeAll(self.space);
+                    try self.stream.writeByte(':');
+                    if (self.whitespace.separator) {
+                        try self.stream.writeByte(' ');
+                    }
                 },
             }
         }
@@ -103,10 +103,12 @@ pub fn WriteStream(comptime OutStream: type, comptime max_depth: usize) type {
                 .ObjectStart => unreachable,
                 .Object => unreachable,
                 .ArrayStart => {
+                    self.whitespace.indent_level -= 1;
                     try self.stream.writeByte(']');
                     self.popState();
                 },
                 .Array => {
+                    self.whitespace.indent_level -= 1;
                     try self.indent();
                     self.popState();
                     try self.stream.writeByte(']');
@@ -121,10 +123,12 @@ pub fn WriteStream(comptime OutStream: type, comptime max_depth: usize) type {
                 .ArrayStart => unreachable,
                 .Array => unreachable,
                 .ObjectStart => {
+                    self.whitespace.indent_level -= 1;
                     try self.stream.writeByte('}');
                     self.popState();
                 },
                 .Object => {
+                    self.whitespace.indent_level -= 1;
                     try self.indent();
                     self.popState();
                     try self.stream.writeByte('}');
@@ -134,17 +138,13 @@ pub fn WriteStream(comptime OutStream: type, comptime max_depth: usize) type {
 
         pub fn emitNull(self: *Self) !void {
             assert(self.state[self.state_index] == State.Value);
-            try self.stream.writeAll("null");
+            try self.stringify(null);
             self.popState();
         }
 
         pub fn emitBool(self: *Self, value: bool) !void {
             assert(self.state[self.state_index] == State.Value);
-            if (value) {
-                try self.stream.writeAll("true");
-            } else {
-                try self.stream.writeAll("false");
-            }
+            try self.stringify(value);
             self.popState();
         }
 
@@ -185,57 +185,19 @@ pub fn WriteStream(comptime OutStream: type, comptime max_depth: usize) type {
         }
 
         fn writeEscapedString(self: *Self, string: []const u8) !void {
-            try self.stream.writeByte('"');
-            for (string) |s| {
-                switch (s) {
-                    '"' => try self.stream.writeAll("\\\""),
-                    '\t' => try self.stream.writeAll("\\t"),
-                    '\r' => try self.stream.writeAll("\\r"),
-                    '\n' => try self.stream.writeAll("\\n"),
-                    8 => try self.stream.writeAll("\\b"),
-                    12 => try self.stream.writeAll("\\f"),
-                    '\\' => try self.stream.writeAll("\\\\"),
-                    else => try self.stream.writeByte(s),
-                }
-            }
-            try self.stream.writeByte('"');
+            assert(std.unicode.utf8ValidateSlice(string));
+            try self.stringify(string);
         }
 
         /// Writes the complete json into the output stream
         pub fn emitJson(self: *Self, json: std.json.Value) Stream.Error!void {
-            switch (json) {
-                .Null => try self.emitNull(),
-                .Bool => |inner| try self.emitBool(inner),
-                .Integer => |inner| try self.emitNumber(inner),
-                .Float => |inner| try self.emitNumber(inner),
-                .String => |inner| try self.emitString(inner),
-                .Array => |inner| {
-                    try self.beginArray();
-                    for (inner.span()) |elem| {
-                        try self.arrayElem();
-                        try self.emitJson(elem);
-                    }
-                    try self.endArray();
-                },
-                .Object => |inner| {
-                    try self.beginObject();
-                    var it = inner.iterator();
-                    while (it.next()) |entry| {
-                        try self.objectField(entry.key);
-                        try self.emitJson(entry.value);
-                    }
-                    try self.endObject();
-                },
-            }
+            try self.stringify(json);
         }
 
         fn indent(self: *Self) !void {
             assert(self.state_index >= 1);
-            try self.stream.writeAll(self.newline);
-            var i: usize = 0;
-            while (i < self.state_index - 1) : (i += 1) {
-                try self.stream.writeAll(self.one_indent);
-            }
+            try self.stream.writeByte('\n');
+            try self.whitespace.outputIndent(self.stream);
         }
 
         fn pushState(self: *Self, state: State) void {
@@ -246,6 +208,12 @@ pub fn WriteStream(comptime OutStream: type, comptime max_depth: usize) type {
         fn popState(self: *Self) void {
             self.state_index -= 1;
         }
+
+        fn stringify(self: *Self, value: var) !void {
+            try std.json.stringify(value, std.json.StringifyOptions{
+                .whitespace = self.whitespace,
+            }, self.stream);
+        }
     };
 }