fix(run): open .NET Project configurations as the form with a project field (#2757)

The .NET Project type had no way back from a command line to its fields, and a
new configuration starts without params, so the editor fell back to the plain
Command/Arguments form: there was no .NET project field, and Debug failed with
"Select a .NET project". dotnet run command lines the form can express now map
back to its fields, for new configurations and ones typed as a command.

Fixes #2733

src/features/run/dotnetTypes.test.tsx

@@ -6,7 +6,7 @@ import { useProject } from "@/platform/project";
 import { dotnetBuildConfig, dotnetProjectType, dotnetTestType } from "./dotnetTypes";
 import { ConfigForm } from "./ConfigForm";
 import { validateConfig } from "./configs";
-import { newConfigOfType, registerBuiltinTypes, withParams } from "./types";
+import { formParams, newConfigOfType, registerBuiltinTypes, withParams } from "./types";
 
 const resolveDotnet = vi.hoisted(() => vi.fn());
 vi.mock("@/platform/ipc", async (importOriginal) => {
@@ -69,6 +69,36 @@ describe(".NET configurations", () => {
     ]);
   });
 
+  it("opens a new configuration, and a typed dotnet run command, as the form with its project field", () => {
+    const fresh = newConfigOfType(dotnetProjectType, []);
+    expect(formParams(fresh, dotnetProjectType)).toEqual({ project: "" });
+    render(
+      <ConfigForm
+        config={fresh}
+        all={[fresh]}
+        type={dotnetProjectType}
+        errors={{}}
+        modifyRequest={0}
+        onChange={vi.fn()}
+      />,
+    );
+    expect(screen.getByLabelText(".NET project")).toBeTruthy();
+    // #2733: typed into the command fields of a configuration without params.
+    const typed: RunConfig = {
+      ...fresh,
+      params: {},
+      command: "dotnet",
+      args: ["run", "--project", "Worker.Service", "--no-launch-profile", "--", "--verbose"],
+    };
+    expect(formParams(typed, dotnetProjectType)).toEqual({
+      project: "Worker.Service",
+      programArgs: "--verbose",
+    });
+    // Options the form has no field for keep the command editor.
+    expect(formParams({ ...typed, args: ["run", "--project", "A", "--no-build"] }, dotnetProjectType)).toBeNull();
+    expect(formParams({ ...typed, args: ["build", "A"] }, dotnetProjectType)).toBeNull();
+  });
+
   it("builds edited project/framework from the open root instead of a profile cwd", () => {
     useProject.setState({ project: { root: "/repo" } as never });
     const c = withParams(

src/features/run/dotnetTypes.ts

@@ -1,7 +1,8 @@
 import { call, commands, type RunConfig } from "@/platform/ipc";
 import { useProject } from "@/platform/project";
 import type { RunConfigTypeContribution } from "@/workbench/contributions";
-import { parseArgs } from "./configs";
+import { formatArgs, parseArgs } from "./configs";
+import { commandName } from "./commandName";
 import { prepareDotnetTest } from "@/platform/dotnet";
 
 function profile(p: Readonly<Record<string, string>>): {
@@ -28,6 +29,38 @@ export function dotnetCommand(p: Readonly<Record<string, string>>, test = false)
   };
 }
 
+/**
+ * The form fields of a `dotnet run` command line ([`dotnetCommand`] reversed), or `null` when it
+ * uses anything the form can't show. Lets a new configuration, and one typed as a command, open
+ * as the form with its project field.
+ */
+function dotnetRunParams(c: RunConfig): Record<string, string> | null {
+  if (!/^dotnet(\.exe)?$/i.test(commandName(c.command))) return null;
+  const [verb, ...rest] = c.args;
+  if (verb !== "run") return null;
+  const p: Record<string, string> = c.command === "dotnet" ? {} : { executable: c.command };
+  const flags: Record<string, string> = {
+    "--project": "project",
+    "--framework": "framework",
+    "--configuration": "configuration",
+    "--launch-profile": "launchProfile",
+  };
+  for (let i = 0; i < rest.length; i++) {
+    const arg = rest[i]!;
+    if (arg === "--") {
+      p.programArgs = formatArgs(rest.slice(i + 1));
+      break;
+    }
+    if (arg === "--no-launch-profile") continue;
+    const key = flags[arg];
+    const value = rest[i + 1];
+    if (!key || value === undefined) return null;
+    p[key] = value;
+    i++;
+  }
+  return { project: "", ...p };
+}
+
 /** Build the current project/framework, independently of the run's profile working directory. */
 export function dotnetBuildConfig(config: RunConfig): RunConfig {
   const p = config.params ?? {};
@@ -104,6 +137,7 @@ export const dotnetProjectType: RunConfigTypeContribution = {
     },
   ],
   commandLine: (p) => dotnetCommand(p),
+  paramsFrom: dotnetRunParams,
   async prepareLaunch(config) {
     const resolved = await call(commands.runDotnetResolve(config, false));
     const p = resolved.params ?? {};