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-rw-r--r--test/behavior/pointers.zig339
1 files changed, 339 insertions, 0 deletions
diff --git a/test/behavior/pointers.zig b/test/behavior/pointers.zig
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+const std = @import("std");
+const testing = std.testing;
+const expect = testing.expect;
+const expectError = testing.expectError;
+
+test "dereference pointer" {
+ comptime testDerefPtr();
+ testDerefPtr();
+}
+
+fn testDerefPtr() void {
+ var x: i32 = 1234;
+ var y = &x;
+ y.* += 1;
+ expect(x == 1235);
+}
+
+const Foo1 = struct {
+ x: void,
+};
+
+test "dereference pointer again" {
+ testDerefPtrOneVal();
+ comptime testDerefPtrOneVal();
+}
+
+fn testDerefPtrOneVal() void {
+ // Foo1 satisfies the OnePossibleValueYes criteria
+ const x = &Foo1{ .x = {} };
+ const y = x.*;
+ expect(@TypeOf(y.x) == void);
+}
+
+test "pointer arithmetic" {
+ var ptr: [*]const u8 = "abcd";
+
+ expect(ptr[0] == 'a');
+ ptr += 1;
+ expect(ptr[0] == 'b');
+ ptr += 1;
+ expect(ptr[0] == 'c');
+ ptr += 1;
+ expect(ptr[0] == 'd');
+ ptr += 1;
+ expect(ptr[0] == 0);
+ ptr -= 1;
+ expect(ptr[0] == 'd');
+ ptr -= 1;
+ expect(ptr[0] == 'c');
+ ptr -= 1;
+ expect(ptr[0] == 'b');
+ ptr -= 1;
+ expect(ptr[0] == 'a');
+}
+
+test "double pointer parsing" {
+ comptime expect(PtrOf(PtrOf(i32)) == **i32);
+}
+
+fn PtrOf(comptime T: type) type {
+ return *T;
+}
+
+test "assigning integer to C pointer" {
+ var x: i32 = 0;
+ var ptr: [*c]u8 = 0;
+ var ptr2: [*c]u8 = x;
+}
+
+test "implicit cast single item pointer to C pointer and back" {
+ var y: u8 = 11;
+ var x: [*c]u8 = &y;
+ var z: *u8 = x;
+ z.* += 1;
+ expect(y == 12);
+}
+
+test "C pointer comparison and arithmetic" {
+ const S = struct {
+ fn doTheTest() void {
+ var one: usize = 1;
+ var ptr1: [*c]u32 = 0;
+ var ptr2 = ptr1 + 10;
+ expect(ptr1 == 0);
+ expect(ptr1 >= 0);
+ expect(ptr1 <= 0);
+ // expect(ptr1 < 1);
+ // expect(ptr1 < one);
+ // expect(1 > ptr1);
+ // expect(one > ptr1);
+ expect(ptr1 < ptr2);
+ expect(ptr2 > ptr1);
+ expect(ptr2 >= 40);
+ expect(ptr2 == 40);
+ expect(ptr2 <= 40);
+ ptr2 -= 10;
+ expect(ptr1 == ptr2);
+ }
+ };
+ S.doTheTest();
+ comptime S.doTheTest();
+}
+
+test "peer type resolution with C pointers" {
+ var ptr_one: *u8 = undefined;
+ var ptr_many: [*]u8 = undefined;
+ var ptr_c: [*c]u8 = undefined;
+ var t = true;
+ var x1 = if (t) ptr_one else ptr_c;
+ var x2 = if (t) ptr_many else ptr_c;
+ var x3 = if (t) ptr_c else ptr_one;
+ var x4 = if (t) ptr_c else ptr_many;
+ expect(@TypeOf(x1) == [*c]u8);
+ expect(@TypeOf(x2) == [*c]u8);
+ expect(@TypeOf(x3) == [*c]u8);
+ expect(@TypeOf(x4) == [*c]u8);
+}
+
+test "implicit casting between C pointer and optional non-C pointer" {
+ var slice: []const u8 = "aoeu";
+ const opt_many_ptr: ?[*]const u8 = slice.ptr;
+ var ptr_opt_many_ptr = &opt_many_ptr;
+ var c_ptr: [*c]const [*c]const u8 = ptr_opt_many_ptr;
+ expect(c_ptr.*.* == 'a');
+ ptr_opt_many_ptr = c_ptr;
+ expect(ptr_opt_many_ptr.*.?[1] == 'o');
+}
+
+test "implicit cast error unions with non-optional to optional pointer" {
+ const S = struct {
+ fn doTheTest() void {
+ expectError(error.Fail, foo());
+ }
+ fn foo() anyerror!?*u8 {
+ return bar() orelse error.Fail;
+ }
+ fn bar() ?*u8 {
+ return null;
+ }
+ };
+ S.doTheTest();
+ comptime S.doTheTest();
+}
+
+test "initialize const optional C pointer to null" {
+ const a: ?[*c]i32 = null;
+ expect(a == null);
+ comptime expect(a == null);
+}
+
+test "compare equality of optional and non-optional pointer" {
+ const a = @intToPtr(*const usize, 0x12345678);
+ const b = @intToPtr(?*usize, 0x12345678);
+ expect(a == b);
+ expect(b == a);
+}
+
+test "allowzero pointer and slice" {
+ var ptr = @intToPtr([*]allowzero i32, 0);
+ var opt_ptr: ?[*]allowzero i32 = ptr;
+ expect(opt_ptr != null);
+ expect(@ptrToInt(ptr) == 0);
+ var runtime_zero: usize = 0;
+ var slice = ptr[runtime_zero..10];
+ comptime expect(@TypeOf(slice) == []allowzero i32);
+ expect(@ptrToInt(&slice[5]) == 20);
+
+ comptime expect(@typeInfo(@TypeOf(ptr)).Pointer.is_allowzero);
+ comptime expect(@typeInfo(@TypeOf(slice)).Pointer.is_allowzero);
+}
+
+test "assign null directly to C pointer and test null equality" {
+ var x: [*c]i32 = null;
+ expect(x == null);
+ expect(null == x);
+ expect(!(x != null));
+ expect(!(null != x));
+ if (x) |same_x| {
+ @panic("fail");
+ }
+ var otherx: i32 = undefined;
+ expect((x orelse &otherx) == &otherx);
+
+ const y: [*c]i32 = null;
+ comptime expect(y == null);
+ comptime expect(null == y);
+ comptime expect(!(y != null));
+ comptime expect(!(null != y));
+ if (y) |same_y| @panic("fail");
+ const othery: i32 = undefined;
+ comptime expect((y orelse &othery) == &othery);
+
+ var n: i32 = 1234;
+ var x1: [*c]i32 = &n;
+ expect(!(x1 == null));
+ expect(!(null == x1));
+ expect(x1 != null);
+ expect(null != x1);
+ expect(x1.?.* == 1234);
+ if (x1) |same_x1| {
+ expect(same_x1.* == 1234);
+ } else {
+ @panic("fail");
+ }
+ expect((x1 orelse &otherx) == x1);
+
+ const nc: i32 = 1234;
+ const y1: [*c]const i32 = &nc;
+ comptime expect(!(y1 == null));
+ comptime expect(!(null == y1));
+ comptime expect(y1 != null);
+ comptime expect(null != y1);
+ comptime expect(y1.?.* == 1234);
+ if (y1) |same_y1| {
+ expect(same_y1.* == 1234);
+ } else {
+ @compileError("fail");
+ }
+ comptime expect((y1 orelse &othery) == y1);
+}
+
+test "null terminated pointer" {
+ const S = struct {
+ fn doTheTest() void {
+ var array_with_zero = [_:0]u8{ 'h', 'e', 'l', 'l', 'o' };
+ var zero_ptr: [*:0]const u8 = @ptrCast([*:0]const u8, &array_with_zero);
+ var no_zero_ptr: [*]const u8 = zero_ptr;
+ var zero_ptr_again = @ptrCast([*:0]const u8, no_zero_ptr);
+ expect(std.mem.eql(u8, std.mem.spanZ(zero_ptr_again), "hello"));
+ }
+ };
+ S.doTheTest();
+ comptime S.doTheTest();
+}
+
+test "allow any sentinel" {
+ const S = struct {
+ fn doTheTest() void {
+ var array = [_:std.math.minInt(i32)]i32{ 1, 2, 3, 4 };
+ var ptr: [*:std.math.minInt(i32)]i32 = &array;
+ expect(ptr[4] == std.math.minInt(i32));
+ }
+ };
+ S.doTheTest();
+ comptime S.doTheTest();
+}
+
+test "pointer sentinel with enums" {
+ const S = struct {
+ const Number = enum {
+ one,
+ two,
+ sentinel,
+ };
+
+ fn doTheTest() void {
+ var ptr: [*:.sentinel]const Number = &[_:.sentinel]Number{ .one, .two, .two, .one };
+ expect(ptr[4] == .sentinel); // TODO this should be comptime expect, see #3731
+ }
+ };
+ S.doTheTest();
+ comptime S.doTheTest();
+}
+
+test "pointer sentinel with optional element" {
+ const S = struct {
+ fn doTheTest() void {
+ var ptr: [*:null]const ?i32 = &[_:null]?i32{ 1, 2, 3, 4 };
+ expect(ptr[4] == null); // TODO this should be comptime expect, see #3731
+ }
+ };
+ S.doTheTest();
+ comptime S.doTheTest();
+}
+
+test "pointer sentinel with +inf" {
+ const S = struct {
+ fn doTheTest() void {
+ const inf = std.math.inf_f32;
+ var ptr: [*:inf]const f32 = &[_:inf]f32{ 1.1, 2.2, 3.3, 4.4 };
+ expect(ptr[4] == inf); // TODO this should be comptime expect, see #3731
+ }
+ };
+ S.doTheTest();
+ comptime S.doTheTest();
+}
+
+test "pointer to array at fixed address" {
+ const array = @intToPtr(*volatile [1]u32, 0x10);
+ // Silly check just to reference `array`
+ expect(@ptrToInt(&array[0]) == 0x10);
+}
+
+test "pointer arithmetic affects the alignment" {
+ {
+ var ptr: [*]align(8) u32 = undefined;
+ var x: usize = 1;
+
+ expect(@typeInfo(@TypeOf(ptr)).Pointer.alignment == 8);
+ const ptr1 = ptr + 1; // 1 * 4 = 4 -> lcd(4,8) = 4
+ expect(@typeInfo(@TypeOf(ptr1)).Pointer.alignment == 4);
+ const ptr2 = ptr + 4; // 4 * 4 = 16 -> lcd(16,8) = 8
+ expect(@typeInfo(@TypeOf(ptr2)).Pointer.alignment == 8);
+ const ptr3 = ptr + 0; // no-op
+ expect(@typeInfo(@TypeOf(ptr3)).Pointer.alignment == 8);
+ const ptr4 = ptr + x; // runtime-known addend
+ expect(@typeInfo(@TypeOf(ptr4)).Pointer.alignment == 4);
+ }
+ {
+ var ptr: [*]align(8) [3]u8 = undefined;
+ var x: usize = 1;
+
+ const ptr1 = ptr + 17; // 3 * 17 = 51
+ expect(@typeInfo(@TypeOf(ptr1)).Pointer.alignment == 1);
+ const ptr2 = ptr + x; // runtime-known addend
+ expect(@typeInfo(@TypeOf(ptr2)).Pointer.alignment == 1);
+ const ptr3 = ptr + 8; // 3 * 8 = 24 -> lcd(8,24) = 8
+ expect(@typeInfo(@TypeOf(ptr3)).Pointer.alignment == 8);
+ const ptr4 = ptr + 4; // 3 * 4 = 12 -> lcd(8,12) = 4
+ expect(@typeInfo(@TypeOf(ptr4)).Pointer.alignment == 4);
+ }
+}
+
+test "@ptrToInt on null optional at comptime" {
+ {
+ const pointer = @intToPtr(?*u8, 0x000);
+ const x = @ptrToInt(pointer);
+ comptime expect(0 == @ptrToInt(pointer));
+ }
+ {
+ const pointer = @intToPtr(?*u8, 0xf00);
+ comptime expect(0xf00 == @ptrToInt(pointer));
+ }
+}
+
+test "indexing array with sentinel returns correct type" {
+ var s: [:0]const u8 = "abc";
+ testing.expectEqualSlices(u8, "*const u8", @typeName(@TypeOf(&s[0])));
+}
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