ludic.wildlife: pin every transition of the 15 WILD_* states and the dice each draws (phase 27.2a)

Sixteen test programs under tests/*_pins_test.ludic, on today's code, each one tick from a set
state through the public step (wildlife_tick_ground / _bird / wildlife_tick, wildlife_release,
wildlife_new): the state it goes to, its timer, and how many of the package's rolls it took and
which (the next roll is read off a newborn's yaw, compared with a stream of the same seed). IDLE,
WANDER, ALERT, WARY, FLEE, CHARGE, GO_DRINK, GO_FEED, DRINK, APPROACH, EAT, TRAPPED, FLY, LAND,
PERCH; the droppings' roll before them; the newborn's seven (eight for a bird); what the step
leaves alone. tests/pin/ holds the shared step, the dice reader and two species of its own (a tame
horse, a crow that never lands on its own). Compiled, not run here: 27.2 holds to them unchanged.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/ludic.wildlife/tests/perch_pins_test.ludic

@@ -0,0 +1,82 @@
+# perch_pins_test.ludic - phase 27.2a: a bird coming down and on the ground as it stands. Gliding in,
+# down and within 2 m it PERCHes for 8 + 16 r0 s; anyone within its flee, or 20 s over its time,
+# lifts it (FLY, 20 + 40 r0 s); on the ground its time up or anyone within its flee lifts it too
+import "ludic.wildlife"
+import "ludic.base"
+import "fake"
+import "pin"
+program PerchPins {
+  numbers float
+  bind WildlifeWorld {
+    ground: fn fk_ground
+    water: fn fk_water
+    players: fn fk_players
+    player_on: fn fk_player_on
+    player_x: fn fk_x
+    player_y: fn fk_y
+    player_z: fn fk_z
+    about: fn fk_about_of
+    lures: fn fk_count
+    lure: fn fk_lure
+    present: fn fk_present
+    spot: fn pn_spot
+    taught: fn pn_taught
+  }
+
+  function bird(wildlife_st: mut WildlifeState, state: int, timer: float, fly_h: float) -> WildAnimal {
+    let a = pn_at(wildlife_st, 3, 0.0, 0.0, state, timer)
+    a.fly_h = fly_h
+    wildlife_seed(wildlife_st, 17)
+    pn_fly(wildlife_st, a)
+    return a
+  }
+
+  test "LAND, down and at its spot: PERCH for 8 + 16 r0 s, one roll" (wildlife_st: mut WildlifeState, wildlife_tests_fake_st: mut WildlifeTestsFakeState) {
+    pn_setup(wildlife_st, wildlife_tests_fake_st)
+    let a = bird(wildlife_st, WILD_LAND, 20.0, 0.1)
+    expect_eq(a.state, WILD_PERCH)
+    expect_near(a.timer, 8.0 + 16.0 * pn_roll(17, 0), 0.0001)
+    expect_near(a.fly_h, 0.0, 0.00001)
+    expect_eq(pn_drew(wildlife_st, 17), 1)
+  }
+
+  test "LAND still high: gliding on, no roll" (wildlife_st: mut WildlifeState, wildlife_tests_fake_st: mut WildlifeTestsFakeState) {
+    pn_setup(wildlife_st, wildlife_tests_fake_st)
+    let a = bird(wildlife_st, WILD_LAND, 20.0, 5.0)
+    expect_eq(a.state, WILD_LAND)
+    expect_near(a.fly_h, 5.0 - 0.05 * 3.2, 0.0001)
+    expect_eq(pn_drew(wildlife_st, 17), 0)
+  }
+
+  test "LAND with somebody within its flee, or 20 s past its time: FLY for 20 + 40 r0 s at the height it had" (wildlife_st: mut WildlifeState, wildlife_tests_fake_st: mut WildlifeTestsFakeState) {
+    pn_setup(wildlife_st, wildlife_tests_fake_st)
+    let b = bird(wildlife_st, WILD_LAND, -19.99, 5.0)
+    expect_eq(b.state, WILD_FLY)
+    expect_near(b.fly_h, 5.0 - 0.05 * 3.2, 0.0001)
+    pn_player(wildlife_tests_fake_st, 5.0, 0.0)
+    let a = bird(wildlife_st, WILD_LAND, 20.0, 5.0)
+    expect_eq(a.state, WILD_FLY)
+    expect_near(a.timer, 20.0 + 40.0 * pn_roll(17, 0), 0.0001)
+    expect_eq(pn_drew(wildlife_st, 17), 1)
+  }
+
+  test "PERCH, its time up or somebody within its flee: FLY for 20 + 40 r0 s, 0.5 m up" (wildlife_st: mut WildlifeState, wildlife_tests_fake_st: mut WildlifeTestsFakeState) {
+    pn_setup(wildlife_st, wildlife_tests_fake_st)
+    let a = bird(wildlife_st, WILD_PERCH, 0.01, 0.0)
+    expect_eq(a.state, WILD_FLY)
+    expect_near(a.timer, 20.0 + 40.0 * pn_roll(17, 0), 0.0001)
+    expect_near(a.fly_h, 0.5, 0.0001)
+    pn_player(wildlife_tests_fake_st, 5.0, 0.0)
+    let b = bird(wildlife_st, WILD_PERCH, 5.0, 0.0)
+    expect_eq(b.state, WILD_FLY)
+    expect_eq(pn_drew(wildlife_st, 17), 1)
+  }
+
+  test "PERCH before its time, nobody near: stays, no roll" (wildlife_st: mut WildlifeState, wildlife_tests_fake_st: mut WildlifeTestsFakeState) {
+    pn_setup(wildlife_st, wildlife_tests_fake_st)
+    let a = bird(wildlife_st, WILD_PERCH, 5.0, 0.0)
+    expect_eq(a.state, WILD_PERCH)
+    expect_near(a.timer, 4.95, 0.0001)
+    expect_eq(pn_drew(wildlife_st, 17), 0)
+  }
+}