test(nes): consolidate and simplify inline subsystem unit tests

src/system/nes/apu/envelope.zig

@@ -108,7 +108,7 @@ pub fn output(self: *const Envelope) u4 {
         self.decay_level;
 }
 
-// ponytail: consolidated envelope generator unit test suite
+// consolidated envelope generator unit test suite
 test "envelope register write, quarter-frame clocking, decay and loop" {
     var envelope = Envelope.init();
     envelope.write(0b0010_1010); // loop=1, const_vol=0, vol=10

src/system/nes/apu/frame_counter.zig

@@ -212,13 +212,13 @@ pub fn irqAsserted(self: *const FrameCounter) bool {
 }
 
 pub fn clearIrq(self: *FrameCounter) void {
-    // ponytail: simultaneous read and IRQ set does not clear flag
+    // simultaneous read and IRQ set does not clear flag
     if (!self.irq_just_set) {
         self.irq_flag = false;
     }
 }
 
-// ponytail: consolidated frame counter unit test suite
+// consolidated frame counter unit test suite
 test "frame counter 4-step and 5-step mode timings, irq window and write delays" {
     var fc = FrameCounter.init(.ntsc);
 

src/system/nes/apu/length_counter.zig

@@ -55,7 +55,7 @@ pub fn active(self: *const LengthCounter) bool {
     return self.value != 0;
 }
 
-// ponytail: consolidated length counter unit test suite
+// consolidated length counter unit test suite
 test "length counter enable, loading, immediate clearing, clocking and halt" {
     try std.testing.expectEqual(@as(u8, 10), table[0]);
 

src/system/nes/apu/noise.zig

@@ -146,7 +146,7 @@ pub fn reset(self: *Noise) void {
     self.length_counter.setEnabled(false);
 }
 
-// ponytail: consolidated noise unit test suite
+// consolidated noise unit test suite
 test "noise channel control, period, length and LFSR shift register" {
     var noise = Noise.init(.ntsc);
     noise.writeControl(0b0011_1010);

src/system/nes/apu/pulse.zig

@@ -253,7 +253,7 @@ pub fn sequencePosition(self: *const Pulse) u3 {
     return self.sequence_position;
 }
 
-// ponytail: consolidated pulse unit test suite
+// consolidated pulse unit test suite
 test "pulse channel register writes, timing, duty sequences and output gating" {
     var pulse = Pulse.init(.pulse1);
 

src/system/nes/apu/root.zig

@@ -68,7 +68,7 @@ pub fn init(region: Region) Apu {
 }
 
 pub fn reset(self: *Apu) void {
-    // ponytail: reset silences all channels and clears APU state
+    // reset silences all channels and clears APU state
     self.writeStatus(0);
     self.frame_counter.reset();
     self.noise.reset();
@@ -286,7 +286,7 @@ pub fn clockCpu(self: *Apu) void {
         self.clockHalfFrame();
     }
 
-    // ponytail: audio downsampler (~40.58 CPU cycles per 44.1kHz sample) with 1st-order DC blocker
+    // audio downsampler (~40.58 CPU cycles per 44.1kHz sample) with 1st-order DC blocker
     self.sample_accumulator += self.output();
     self.sample_cycles += 1;
     if (self.sample_cycles >= 40) {
@@ -463,7 +463,7 @@ pub fn output(self: *const Apu) f32 {
     return pulse_out + tnd_out;
 }
 
-// ponytail: consolidated APU root test suite
+// consolidated APU root test suite
 test "apu initialization, status reads, IRQ clearing, sample generation and DMC DMA" {
     var apu = Apu.init(.ntsc);
 

src/system/nes/apu/sweep.zig

@@ -143,7 +143,7 @@ pub fn clockHalfFrame(
     }
 }
 
-// ponytail: consolidated sweep unit test suite
+// consolidated sweep unit test suite
 test "sweep unit target calculation, gating and clocking" {
     var sweep1 = Sweep.init(.pulse1);
     sweep1.write(0b1010_0001); // P=2, shift=1

src/system/nes/bus.zig

@@ -183,7 +183,7 @@ pub fn irqLine(self: *const Bus) bool {
     return apu_irq or cart_irq;
 }
 
-// ponytail: consolidated bus memory mirroring test suite
+// consolidated bus memory mirroring test suite
 test "bus internal RAM and CIRAM nametable mirroring" {
     var bus = Bus.init(.ntsc, null);
     bus.write(0x0005, 0x99);

src/system/nes/controller.zig

@@ -45,7 +45,7 @@ pub fn read(self: *Controller) u8 {
     return val | 0x40;
 }
 
-// ponytail: consolidated controller test suite
+// consolidated controller test suite
 test "controller strobe and serial shift read" {
     var c = Controller.init();
     c.setButtons(0x09); // A and Start pressed

src/system/nes/mapper/action53.zig

@@ -2,7 +2,7 @@ const std = @import("std");
 const common = @import("../common.zig");
 const Mirroring = common.Mirroring;
 
-// ponytail: Mapper 28 (Action 53)
+// Mapper 28 (Action 53)
 pub const Action53 = @This();
 
 selected_reg: u2 = 0,

src/system/nes/mapper/bnrom.zig

@@ -2,7 +2,7 @@ const std = @import("std");
 const common = @import("../common.zig");
 const Mirroring = common.Mirroring;
 
-// ponytail: Mapper 34 (BNROM / NINA-001) - 32KB PRG banking, optional NINA-001 4KB CHR banking
+// Mapper 34 (BNROM / NINA-001) - 32KB PRG banking, optional NINA-001 4KB CHR banking
 pub const Bnrom = @This();
 
 prg_bank: u8 = 0,

src/system/nes/mapper/camerica.zig

@@ -2,7 +2,7 @@ const std = @import("std");
 const common = @import("../common.zig");
 const Mirroring = common.Mirroring;
 
-// ponytail: Mapper 71 (Camerica / Codemasters) - 16KB PRG banking at $C000-$FFFF, optional 1-screen mirroring at $9000-$9FFF
+// Mapper 71 (Camerica / Codemasters) - 16KB PRG banking at $C000-$FFFF, optional 1-screen mirroring at $9000-$9FFF
 pub const Camerica = @This();
 
 prg_bank: u8 = 0,

src/system/nes/mapper/cnrom.zig

@@ -35,7 +35,7 @@ pub fn cpuWrite(self: *Cnrom, address: u16, value: u8, prg_ram: []u8) bool {
         }
     }
     if (address >= 0x8000 and address <= 0xffff) {
-        // ponytail: mask up to 16 banks (128KB) for extended CNROM homebrew
+        // mask up to 16 banks (128KB) for extended CNROM homebrew
         self.chr_bank = value & 0x0f;
         return true;
     }

src/system/nes/mapper/color_dreams.zig

@@ -2,7 +2,7 @@ const std = @import("std");
 const common = @import("../common.zig");
 const Mirroring = common.Mirroring;
 
-// ponytail: Mapper 11 (Color Dreams) - 32KB PRG bank in bits 0-1, 8KB CHR bank in bits 4-7
+// Mapper 11 (Color Dreams) - 32KB PRG bank in bits 0-1, 8KB CHR bank in bits 4-7
 pub const ColorDreams = @This();
 
 prg_bank: u8 = 0,

src/system/nes/mapper/gxrom.zig

@@ -2,7 +2,7 @@ const std = @import("std");
 const common = @import("../common.zig");
 const Mirroring = common.Mirroring;
 
-// ponytail: Mapper 66 (GxROM / GNROM) - 32KB PRG bank in bits 4-5, 8KB CHR bank in bits 0-1
+// Mapper 66 (GxROM / GNROM) - 32KB PRG bank in bits 4-5, 8KB CHR bank in bits 0-1
 pub const Gxrom = @This();
 
 prg_bank: u8 = 0,

src/system/nes/mapper/mapper180.zig

@@ -2,7 +2,7 @@ const std = @import("std");
 const common = @import("../common.zig");
 const Mirroring = common.Mirroring;
 
-// ponytail: Mapper 180 (Nichibutsu / Crazy Climber)
+// Mapper 180 (Nichibutsu / Crazy Climber)
 // Fixed first 16KB at $8000-$BFFF, switchable 16KB at $C000-$FFFF via write to $8000-$FFFF.
 pub const Mapper180 = @This();
 

src/system/nes/mapper/mmc1.zig

@@ -25,7 +25,7 @@ pub fn cpuRead(self: *const Mmc1, address: u16, prg_rom: []const u8, prg_ram: []
     if (address >= 0x8000 and address <= 0xffff) {
         const prg_mode: u2 = @truncate(self.control >> 2);
         const total_16k_banks: usize = @max(1, prg_rom.len / 0x4000);
-        // ponytail: SUROM uses CHR bank 0 bit 4 for PRG A18 when PRG is 512KB
+        // SUROM uses CHR bank 0 bit 4 for PRG A18 when PRG is 512KB
         const surom_base: usize = if (total_16k_banks >= 32 and (self.chr_bank_0 & 0x10) != 0) 16 else 0;
         var bank: usize = 0;
 

src/system/nes/mapper/mmc2.zig

@@ -2,7 +2,7 @@ const std = @import("std");
 const common = @import("../common.zig");
 const Mirroring = common.Mirroring;
 
-// ponytail: Mapper 9 (MMC2) - Mike Tyson's Punch-Out!!
+// Mapper 9 (MMC2) - Mike Tyson's Punch-Out!!
 // 8KB switchable PRG at $8000, fixed 24KB at $A000-$FFFF.
 // Dual 4KB CHR latches toggled by PPU fetches at $xFD8-$xFDF and $xFE8-$xFEF.
 pub const Mmc2 = @This();

src/system/nes/mapper/mmc4.zig

@@ -2,7 +2,7 @@ const std = @import("std");
 const common = @import("../common.zig");
 const Mirroring = common.Mirroring;
 
-// ponytail: Mapper 10 (MMC4) - Fire Emblem & Fire Emblem Gaiden
+// Mapper 10 (MMC4) - Fire Emblem & Fire Emblem Gaiden
 // 16KB switchable PRG at $8000, fixed last 16KB at $C000-$FFFF.
 // Dual 4KB CHR latches toggled by PPU fetches at $xFD8-$xFDF and $xFE8-$xFEF.
 pub const Mmc4 = @This();

src/system/nes/mapper/unrom512.zig

@@ -2,7 +2,7 @@ const std = @import("std");
 const common = @import("../common.zig");
 const Mirroring = common.Mirroring;
 
-// ponytail: Mapper 30 (UNROM-512) - 16KB PRG bank (bits 0-4), 8KB CHR-RAM bank (bits 5-6), 1-screen mirroring (bit 7)
+// Mapper 30 (UNROM-512) - 16KB PRG bank (bits 0-4), 8KB CHR-RAM bank (bits 5-6), 1-screen mirroring (bit 7)
 pub const Unrom512 = @This();
 
 prg_bank: u8 = 0,

src/system/nes/mapper/uxrom.zig

@@ -43,7 +43,7 @@ pub fn cpuWrite(self: *Uxrom, address: u16, value: u8, prg_ram: []u8) bool {
         }
     }
     if (address >= 0x8000 and address <= 0xffff) {
-        // ponytail: mask up to 32 banks (512KB) for UOROM / UNROM
+        // mask up to 32 banks (512KB) for UOROM / UNROM
         self.prg_bank = value & 0x1f;
         return true;
     }

src/system/nes/ppu/registers.zig

@@ -263,11 +263,15 @@ pub fn cpuWrite(self: *Registers, bus: anytype, address: u16, value: u8, renderi
     return true;
 }
 
-// ponytail: consolidated PPU registers test suite
+// consolidated PPU registers test suite
 pub const TestBus = struct {
     memory: [0x10000]u8 = [_]u8{0} ** 0x10000,
-    pub fn read(self: *TestBus, address: u16) u8 { return self.memory[address]; }
+    pub fn read(self: *TestBus, address: u16) u8 {
-    pub fn write(self: *TestBus, address: u16, value: u8) void { self.memory[address] = value; }
+        return self.memory[address];
+    }
+    pub fn write(self: *TestBus, address: u16, value: u8) void {
+        self.memory[address] = value;
+    }
 };
 
 test "ppu registers $2000-$2007 control, scroll, address and buffered reads" {

src/system/nes/ppu/root.zig

@@ -311,7 +311,7 @@ fn stepSpriteLogic(self: *Ppu, bus: anytype) void {
                     }
                     self.sprite_count += 1;
                 } else {
-                    // ponytail: 8-sprite limit reached; set overflow flag
+                    // 8-sprite limit reached; set overflow flag
                     self.registers.setSpriteOverflow(true);
                     break;
                 }
@@ -494,7 +494,7 @@ const MockBus = struct {
     pub fn write(_: *MockBus, _: u16, _: u8) void {}
 };
 
-// ponytail: consolidated PPU timing and rendering unit test suite
+// consolidated PPU timing and rendering unit test suite
 test "ppu scanline progression, vblank flags, odd-frame skip and sprite 0 hit" {
     var ppu = Ppu.init(.ntsc);
     var bus = MockBus{};