test(dbt-tools): add unit tests for build command routing

Covers: no-model → project build, --model → single model, --downstream flag.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: mdesmet

packages/dbt-tools/test/build.test.ts

@@ -0,0 +1,47 @@
+import { describe, test, expect, mock } from "bun:test"
+import { build, project } from "../src/commands/build"
+import type { DBTProjectIntegrationAdapter } from "@altimateai/dbt-integration"
+
+function makeAdapter(overrides: Partial<DBTProjectIntegrationAdapter> = {}): DBTProjectIntegrationAdapter {
+  return {
+    unsafeBuildModelImmediately: mock(() => Promise.resolve({ stdout: "model built", stderr: "" })),
+    unsafeBuildProjectImmediately: mock(() => Promise.resolve({ stdout: "project built", stderr: "" })),
+    unsafeRunModelImmediately: mock(() => Promise.resolve({ stdout: "", stderr: "" })),
+    unsafeRunModelTestImmediately: mock(() => Promise.resolve({ stdout: "", stderr: "" })),
+    dispose: mock(() => Promise.resolve()),
+    ...overrides,
+  } as unknown as DBTProjectIntegrationAdapter
+}
+
+describe("build command", () => {
+  test("build without --model builds entire project", async () => {
+    const adapter = makeAdapter()
+    const result = await build(adapter, [])
+    expect(adapter.unsafeBuildProjectImmediately).toHaveBeenCalledTimes(1)
+    expect(adapter.unsafeBuildModelImmediately).not.toHaveBeenCalled()
+    expect(result).toEqual({ stdout: "project built" })
+  })
+
+  test("build --model <name> builds single model", async () => {
+    const adapter = makeAdapter()
+    const result = await build(adapter, ["--model", "orders"])
+    expect(adapter.unsafeBuildModelImmediately).toHaveBeenCalledTimes(1)
+    expect(adapter.unsafeBuildModelImmediately).toHaveBeenCalledWith({
+      plusOperatorLeft: "",
+      modelName: "orders",
+      plusOperatorRight: "",
+    })
+    expect(adapter.unsafeBuildProjectImmediately).not.toHaveBeenCalled()
+    expect(result).toEqual({ stdout: "model built" })
+  })
+
+  test("build --model <name> --downstream sets plusOperatorRight", async () => {
+    const adapter = makeAdapter()
+    await build(adapter, ["--model", "orders", "--downstream"])
+    expect(adapter.unsafeBuildModelImmediately).toHaveBeenCalledWith({
+      plusOperatorLeft: "",
+      modelName: "orders",
+      plusOperatorRight: "+",
+    })
+  })
+})