Add script to generate nuget.config (#115)

## Description of Changes
Adds a utility script to generate `nuget.config` given a path to the
`SpacetimeDB` repo.

## API
No

## Requires SpacetimeDB PRs
None

## Testing
- [x] CI
- [x] Ran locally

---------

Co-authored-by: Zeke Foppa <[email protected]>

Author: bfops

sdks/csharp/.github/workflows/dotnet.yml

@@ -36,28 +36,9 @@ jobs:
         # available. Otherwise, `spacetimedb-csharp-sdk` will use the NuGet versions of the packages.
         # This means that (if version numbers match) we will test the local versions of the C# packages, even
         # if they're not pushed to NuGet.
-        # See https://learn.microsoft.com/en-us/nuget/reference/nuget-config-file for more info on the config file,
-        # and https://tldp.org/LDP/abs/html/here-docs.html for more info on this bash feature.
-        cat >nuget.config <<EOF
-        <?xml version="1.0" encoding="utf-8"?>
-        <configuration>
-          <packageSources>
-            <!-- Local NuGet repositories -->
-            <add key="Local SpacetimeDB.BSATN.Runtime" value="../SpacetimeDB/crates/bindings-csharp/BSATN.Runtime/bin/Release" />
-          </packageSources>
-          <packageSourceMapping>
-            <!-- Ensure that SpacetimeDB.BSATN.Runtime is used from the local folder. -->
-            <!-- Otherwise we risk an outdated version being quietly pulled from NuGet for testing. -->
-            <packageSource key="Local SpacetimeDB.BSATN.Runtime">
-              <package pattern="SpacetimeDB.BSATN.Runtime" />
-            </packageSource>
-            <!-- Fallback for other packages (e.g. test deps). -->
-            <packageSource key="nuget.org">
-              <package pattern="*" />
-            </packageSource>
-          </packageSourceMapping>
-        </configuration>
-        EOF
+        # See https://learn.microsoft.com/en-us/nuget/reference/nuget-config-file for more info on the config file.
+        ./tools~/write-nuget-config.sh ../SpacetimeDB
+
     - name: Restore dependencies
       working-directory: spacetimedb-csharp-sdk
       run: dotnet restore

sdks/csharp/tests~/README.md

@@ -0,0 +1,20 @@
+# Running tests
+You can use `dotnet test` (either in this directory or in the project root directory) to run the tests.
+
+# Using a different SpacetimeDB version
+To run tests using a local version of the `SpacetimeDB` repo, you can add a `nuget.config` file in the **root** of this repository.
+
+The `tools/write-nuget-config.sh` script can generate the `nuget.config`. It takes one parameter: the path to the root SpacetimeDB repository (relative or absolute).
+
+Then, you need to `dotnet pack` the `BSATN.Runtime` package in the `SpacetimeDB` repo.
+
+Lastly, before running `dotnet test`, you should `dotnet nuget locals all --clear` to clear out any cached packages. This ensures you're actually testing with the new package you just built.
+
+Example:
+```bash
+$ export SPACETIMEDB_REPO_PATH="../SpacetimeDB"
+$ tools/write-nuget-config.sh "${SPACETIMEDB_REPO_PATH}"
+$ ( cd "${SPACETIMEDB_REPO_PATH}"/crates/bindings-csharp/BSATN.Runtime && dotnet pack )
+$ dotnet nuget locals all --clear
+$ dotnet test
+```

sdks/csharp/tools~/write-nuget-config.sh

@@ -0,0 +1,35 @@
+set -ueo pipefail
+
+SPACETIMEDB_REPO_PATH="$1"
+
+cd "$(dirname "$(readlink -f "$0")")"
+cd ..
+
+# Write out the nuget config file to `nuget.config`. This causes the spacetimedb-csharp-sdk repository
+# to be aware of the local versions of the `bindings-csharp` packages in SpacetimeDB, and use them if
+# available.
+# See https://learn.microsoft.com/en-us/nuget/reference/nuget-config-file for more info on the config file,
+# and https://tldp.org/LDP/abs/html/here-docs.html for more info on this bash feature.
+cat >nuget.config <<EOF
+<?xml version="1.0" encoding="utf-8"?>
+<configuration>
+  <packageSources>
+    <!-- Local NuGet repositories -->
+    <add key="Local SpacetimeDB.BSATN.Runtime" value="${SPACETIMEDB_REPO_PATH}/crates/bindings-csharp/BSATN.Runtime/bin/Release" />
+  </packageSources>
+  <packageSourceMapping>
+    <!-- Ensure that SpacetimeDB.BSATN.Runtime is used from the local folder. -->
+    <!-- Otherwise we risk an outdated version being quietly pulled from NuGet for testing. -->
+    <packageSource key="Local SpacetimeDB.BSATN.Runtime">
+      <package pattern="SpacetimeDB.BSATN.Runtime" />
+    </packageSource>
+    <!-- Fallback for other packages (e.g. test deps). -->
+    <packageSource key="nuget.org">
+      <package pattern="*" />
+    </packageSource>
+  </packageSourceMapping>
+</configuration>
+EOF
+
+echo "Wrote nuget.config contents:"
+cat nuget.config