add access to global context to scripty builtins

Author: kristoff-it

src/fuzz/context.zig

@@ -52,14 +52,15 @@ const TestValue = union(Tag) {
         }
     }
 
-    pub const call = scripty.defaultCall(TestValue);
+    pub const call = scripty.defaultCall(TestValue, TestContext);
 
     pub fn builtinsFor(comptime tag: Tag) type {
         const StringBuiltins = struct {
             pub const len = struct {
                 pub fn call(
                     str: []const u8,
                     gpa: std.mem.Allocator,
+                    _: *const TestContext,
                     args: []const TestValue,
                 ) !TestValue {
                     if (args.len != 0) return .{ .err = "'len' wants no arguments" };

src/types.zig

@@ -29,16 +29,18 @@ pub fn defaultDot(
     }.dot;
 }
 
-pub fn defaultCall(comptime Value: type) fn (
+pub fn defaultCall(Value: type, Context: type) fn (
     Value,
     std.mem.Allocator,
+    *const Context,
     []const u8,
     []const Value,
 ) error{ OutOfMemory, Interrupt }!Value {
     return struct {
         pub fn call(
             value: Value,
             gpa: std.mem.Allocator,
+            ctx: *const Context,
             fn_name: []const u8,
             args: []const Value,
         ) error{ OutOfMemory, Interrupt }!Value {
@@ -55,6 +57,7 @@ pub fn defaultCall(comptime Value: type) fn (
                             return @field(Builtin, decl.name).call(
                                 v,
                                 gpa,
+                                ctx,
                                 args,
                             );
                         }
@@ -63,6 +66,7 @@ pub fn defaultCall(comptime Value: type) fn (
                     if (hasDecl(@TypeOf(v), "fallbackCall")) {
                         return v.fallbackCall(
                             gpa,
+                            ctx,
                             fn_name,
                             args,
                         );

src/vm.zig

@@ -257,7 +257,7 @@ pub fn VM(
                         stack_locs[call_idx].start = call_loc.start;
                         stack_locs[call_idx].end = call_loc.end + 1;
 
-                        const new_value = old_value.call(gpa, fn_name, args) catch |err| switch (err) {
+                        const new_value = old_value.call(gpa, ctx, fn_name, args) catch |err| switch (err) {
                             error.OutOfMemory => return error.OutOfMemory,
                             error.Interrupt => {
                                 vm.state = .waiting;
@@ -340,14 +340,15 @@ pub const TestValue = union(Tag) {
         }
     }
 
-    pub const call = types.defaultCall(TestValue);
+    pub const call = types.defaultCall(TestValue, TestContext);
 
     pub fn builtinsFor(comptime tag: Tag) type {
         const StringBuiltins = struct {
             pub const len = struct {
                 pub fn call(
                     str: []const u8,
                     gpa: std.mem.Allocator,
+                    _: *const TestContext,
                     args: []const TestValue,
                 ) !TestValue {
                     if (args.len != 0) return .{
@@ -360,6 +361,7 @@ pub const TestValue = union(Tag) {
                 pub fn call(
                     str: []const u8,
                     gpa: std.mem.Allocator,
+                    _: *const TestContext,
                     args: []const TestValue,
                 ) !TestValue {
                     if (args.len != 0) return .{