T07: Cargo workspace scaffold — cb-kernel/cb-events/cb-game-runtime/games-ground/cb-sim, HashMap deny-lint, scenario format + runner stub, Criterion skeleton, Makefile, CI

crates/cb-game-runtime/src/scenario.rs

@@ -0,0 +1,131 @@
+//! Scenario file format and runner scaffold (MetricsAndScenarios §2,
+//! GameKernel K17). The format parses fully; execution against a game
+//! aggregate is wired up in T08 — until then `run` reports Unimplemented.
+
+use serde::{Deserialize, Serialize};
+use std::collections::BTreeMap;
+
+/// One scenario file (`scenarios/<game>/<slug>.yaml`).
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
+pub struct ScenarioFile {
+    pub scenario: String,
+    #[serde(default)]
+    pub description: String,
+    /// Numbered rule IDs this scenario covers (feeds M-D1-COV / AM-1).
+    pub covers: Vec<String>,
+    /// Marks scenarios encoding a PROVISIONAL U-item default
+    /// (GroundRules §Underdetermined): a ground-game ruling flips the
+    /// scenario, not the kernel.
+    #[serde(default)]
+    pub provisional: bool,
+    pub seed: u64,
+    pub setup: Setup,
+    pub commands: Vec<CommandStep>,
+    pub expect: Expect,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
+pub struct Setup {
+    pub players: u8,
+    /// Named setup preset from the game spec (e.g. "standard-3p").
+    pub preset: String,
+    /// Explicit state overrides applied after the preset (dot-paths).
+    #[serde(default)]
+    pub patch: BTreeMap<String, serde_yaml::Value>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
+pub struct CommandStep {
+    pub actor: String,
+    pub cmd: String,
+    #[serde(default)]
+    pub args: BTreeMap<String, serde_yaml::Value>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, Default)]
+#[serde(deny_unknown_fields)]
+pub struct Expect {
+    /// Ordered subsequence of event kinds that must occur.
+    #[serde(default)]
+    pub events: Vec<BTreeMap<String, serde_yaml::Value>>,
+    /// Partial end-state assertions: dot-path → expected value.
+    #[serde(default)]
+    pub state: BTreeMap<String, serde_yaml::Value>,
+    /// Indices into `commands` that must be rejected.
+    #[serde(default)]
+    pub rejects: Vec<usize>,
+    /// Optional full-state golden hash.
+    #[serde(default)]
+    pub state_hash: Option<String>,
+}
+
+impl ScenarioFile {
+    pub fn from_yaml(yaml: &str) -> Result<Self, serde_yaml::Error> {
+        serde_yaml::from_str(yaml)
+    }
+}
+
+/// Result of executing one scenario (twice, per the K8 double-run rule).
+#[derive(Debug)]
+pub enum RunOutcome {
+    Passed {
+        covers: Vec<String>,
+    },
+    Failed {
+        reason: String,
+    },
+    /// Scaffold state: parsing works, execution lands in T08.
+    Unimplemented,
+}
+
+/// Runner scaffold. T08 replaces the body with: build aggregate from
+/// setup, apply commands via validate/fold, check expectations, run twice
+/// and compare hashes, emit a replay bundle on failure.
+pub fn run(_scenario: &ScenarioFile) -> RunOutcome {
+    RunOutcome::Unimplemented
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    const SAMPLE: &str = r#"
+scenario: ground/smoke-setup
+description: Parses the documented scenario shape end to end.
+covers: [GR-S02, GR-S03]
+provisional: false
+seed: 42
+setup:
+  players: 3
+  preset: standard-3p
+  patch:
+    "players.0.stress": 4
+commands:
+  - actor: P1
+    cmd: select_action
+    args: { action: ATTACK, target: P2 }
+expect:
+  state:
+    "round": 1
+  rejects: []
+"#;
+
+    #[test]
+    fn scenario_format_roundtrips() {
+        let parsed = ScenarioFile::from_yaml(SAMPLE).unwrap();
+        assert_eq!(parsed.scenario, "ground/smoke-setup");
+        assert_eq!(parsed.covers, vec!["GR-S02", "GR-S03"]);
+        assert_eq!(parsed.setup.players, 3);
+        assert_eq!(parsed.commands.len(), 1);
+        assert!(matches!(run(&parsed), RunOutcome::Unimplemented));
+    }
+
+    #[test]
+    fn unknown_fields_are_rejected() {
+        let bad = SAMPLE.replace("seed: 42", "seed: 42\ntypo_field: 1");
+        assert!(ScenarioFile::from_yaml(&bad).is_err());
+    }
+}