Refactor version resolving (#852)

__tests__/download/download-version.test.ts

@@ -95,6 +95,35 @@ describe("download-version", () => {
       expect(mockGetAllVersions).toHaveBeenCalledWith(undefined);
     });
 
+    it("treats == exact pins as explicit versions", async () => {
+      const version = await resolveVersion("==0.9.26", undefined);
+
+      expect(version).toBe("0.9.26");
+      expect(mockGetAllVersions).not.toHaveBeenCalled();
+      expect(mockGetLatestVersion).not.toHaveBeenCalled();
+    });
+
+    it("uses latest for minimum-only ranges when using the highest strategy", async () => {
+      mockGetLatestVersion.mockResolvedValue("0.9.26");
+
+      const version = await resolveVersion(">=0.9.0", undefined, "highest");
+
+      expect(version).toBe("0.9.26");
+      expect(mockGetLatestVersion).toHaveBeenCalledTimes(1);
+      expect(mockGetLatestVersion).toHaveBeenCalledWith(undefined);
+      expect(mockGetAllVersions).not.toHaveBeenCalled();
+    });
+
+    it("uses the lowest compatible version when requested", async () => {
+      mockGetAllVersions.mockResolvedValue(["0.9.26", "0.9.25"]);
+
+      const version = await resolveVersion("^0.9.0", undefined, "lowest");
+
+      expect(version).toBe("0.9.25");
+      expect(mockGetAllVersions).toHaveBeenCalledTimes(1);
+      expect(mockGetAllVersions).toHaveBeenCalledWith(undefined);
+    });
+
     it("uses manifest-file when provided", async () => {
       mockGetAllVersions.mockResolvedValue(["0.9.26", "0.9.25"]);
 

__tests__/version/requirements-file.test.ts

@@ -1,5 +1,5 @@
 import { expect, test } from "@jest/globals";
-import { getUvVersionFromFile } from "../../src/version/resolve";
+import { getUvVersionFromFile } from "../../src/version/file-parser";
 
 test("ignores dependencies starting with uv", async () => {
   const parsedVersion = getUvVersionFromFile(

__tests__/version/requirements-hashes-file.test.ts

@@ -1,5 +1,5 @@
 import { expect, test } from "@jest/globals";
-import { getUvVersionFromFile } from "../../src/version/resolve";
+import { getUvVersionFromFile } from "../../src/version/file-parser";
 
 test("ignores dependencies starting with uv", async () => {
   const parsedVersion = getUvVersionFromFile(

__tests__/version/version-request-resolver.test.ts

@@ -0,0 +1,125 @@
+import fs from "node:fs";
+import os from "node:os";
+import path from "node:path";
+import { afterEach, describe, expect, it } from "@jest/globals";
+import { resolveVersionRequest } from "../../src/version/version-request-resolver";
+
+const tempDirs: string[] = [];
+
+function createTempProject(files: Record<string, string> = {}): string {
+  const dir = fs.mkdtempSync(path.join(os.tmpdir(), "setup-uv-version-test-"));
+  tempDirs.push(dir);
+
+  for (const [relativePath, content] of Object.entries(files)) {
+    const filePath = path.join(dir, relativePath);
+    fs.mkdirSync(path.dirname(filePath), { recursive: true });
+    fs.writeFileSync(filePath, content);
+  }
+
+  return dir;
+}
+
+afterEach(() => {
+  for (const dir of tempDirs.splice(0)) {
+    fs.rmSync(dir, { force: true, recursive: true });
+  }
+});
+
+describe("resolveVersionRequest", () => {
+  it("prefers explicit input over version-file and workspace config", () => {
+    const workingDirectory = createTempProject({
+      ".tool-versions": "uv 0.4.0\n",
+      "pyproject.toml": `[tool.uv]\nrequired-version = "==0.5.14"\n`,
+      "uv.toml": `required-version = "==0.5.15"\n`,
+    });
+
+    const request = resolveVersionRequest({
+      version: "==0.6.0",
+      versionFile: path.join(workingDirectory, ".tool-versions"),
+      workingDirectory,
+    });
+
+    expect(request).toEqual({
+      source: "input",
+      specifier: "0.6.0",
+    });
+  });
+
+  it("uses .tool-versions when it is passed via version-file", () => {
+    const workingDirectory = createTempProject({
+      ".tool-versions": "uv 0.5.15\n",
+    });
+
+    const request = resolveVersionRequest({
+      versionFile: path.join(workingDirectory, ".tool-versions"),
+      workingDirectory,
+    });
+
+    expect(request).toEqual({
+      format: ".tool-versions",
+      source: "version-file",
+      sourcePath: path.join(workingDirectory, ".tool-versions"),
+      specifier: "0.5.15",
+    });
+  });
+
+  it("uses requirements.txt when it is passed via version-file", () => {
+    const workingDirectory = createTempProject({
+      "requirements.txt": "uv==0.6.17\nuvicorn==0.35.0\n",
+    });
+
+    const request = resolveVersionRequest({
+      versionFile: path.join(workingDirectory, "requirements.txt"),
+      workingDirectory,
+    });
+
+    expect(request).toEqual({
+      format: "requirements",
+      source: "version-file",
+      sourcePath: path.join(workingDirectory, "requirements.txt"),
+      specifier: "0.6.17",
+    });
+  });
+
+  it("prefers uv.toml over pyproject.toml during workspace discovery", () => {
+    const workingDirectory = createTempProject({
+      "pyproject.toml": `[tool.uv]\nrequired-version = "==0.5.14"\n`,
+      "uv.toml": `required-version = "==0.5.15"\n`,
+    });
+
+    const request = resolveVersionRequest({ workingDirectory });
+
+    expect(request).toEqual({
+      format: "uv.toml",
+      source: "uv.toml",
+      sourcePath: path.join(workingDirectory, "uv.toml"),
+      specifier: "0.5.15",
+    });
+  });
+
+  it("falls back to latest when no version source is found", () => {
+    const workingDirectory = createTempProject({});
+
+    const request = resolveVersionRequest({ workingDirectory });
+
+    expect(request).toEqual({
+      source: "default",
+      specifier: "latest",
+    });
+  });
+
+  it("throws when version-file does not resolve a version", () => {
+    const workingDirectory = createTempProject({
+      "requirements.txt": "uvicorn==0.35.0\n",
+    });
+
+    expect(() =>
+      resolveVersionRequest({
+        versionFile: path.join(workingDirectory, "requirements.txt"),
+        workingDirectory,
+      }),
+    ).toThrow(
+      `Could not determine uv version from file: ${path.join(workingDirectory, "requirements.txt")}`,
+    );
+  });
+});