cargo-pgrx: fix pg_regress path inconsistency

The 'cargo pgrx new' command was creating pg_regress directories at
the project root (./pg_regress/), while 'cargo pgrx regress' expected
them under the tests directory (./tests/pg_regress/). This
inconsistency caused immediate failures when running regression tests
on newly created projects.

Fix the path mismatch by updating 'cargo pgrx new' to create the
pg_regress directory structure under tests/, aligning with where
'cargo pgrx regress' expects to find them. This follows Rust's
convention of organizing test files in a tests/ directory.

Also update the documentation and the hooks example to use the
consistent path structure.

Fixes: #2136 ("Inconsistencies in the pg_regress path")

Signed-off-by: Charalampos Mitrodimas <[email protected]>

Author: charmitro

cargo-pgrx/README.md

@@ -590,12 +590,12 @@ $ tree
 
 `setup.sql` is a special test in that it's run first, by itself, whenever the test database is first created, or reset using the `--resetdb` argument.
 
-When creating a new test, first make the `.sql` file in `./pg_regress/sql/` and then run `cargo pgrx regress`.  pgrx will detect that the file is new and interactively prompt you to add its output, automatically adding it to git (if the directory is managed by git).
+When creating a new test, first make the `.sql` file in `./tests/pg_regress/sql/` and then run `cargo pgrx regress`.  pgrx will detect that the file is new and interactively prompt you to add its output, automatically adding it to git (if the directory is managed by git).
 
 For example,
 
 ```console
-$ echo "SELECT 1;" > ./pg_regress/sql/example.sql
+$ echo "SELECT 1;" > ./tests/pg_regress/sql/example.sql
 $ cargo pgrx regress                             
        Using DefaultFeature("pg13") and `pg_config` from  ~/.pgrx/13.20/pgrx-install/bin/pg_config
     Stopping Postgres v13
@@ -627,7 +627,7 @@ test `example` generated the above output:
 Accept [Y, n]? 
 ```
 
-Typing `Y` (or just pressing return) will copy the test output to the proper location, `./pg_regress/expected/example.sql` and then run the entire test suite:
+Typing `Y` (or just pressing return) will copy the test output to the proper location, `./tests/pg_regress/expected/example.out` and then run the entire test suite:
 
 ```console
 ...
@@ -657,7 +657,7 @@ Alternatively, you can run `cargo pgrx regress --auto` (or `-a`) to **automatica
 - tests are executed in alphabetical order
 - pgrx creates a database named `$extname_regress` unless `--dbname` is used
 - Postgres' documentation for `pg_regress` [begins here](https://www.postgresql.org/docs/current/regress.html).  While pgrx does not support every knob and dial, its organization is largely compatible (PRs welcome to enhance features)
-- to regenerate the expected test output, delete the `./pg_regress/expected/TEST_NAME.out` file and run `cargo pgrx regress`.  You'll be prompted to accept the new output and it'll automatically be run through `git add`
+- to regenerate the expected test output, delete the `./tests/pg_regress/expected/TEST_NAME.out` file and run `cargo pgrx regress`.  You'll be prompted to accept the new output and it'll automatically be run through `git add`
 - `pg_regress` uses `psql` to run each test and literally diffs the output against the expected output file.  pgrx does two things to help eliminate noise in the test output.  The first is it sets `client_min_messages=warning` when starting the Postgres instance and it also passes `-v VERBOSITY=terse` through to `psql`.   
 
 ### Diffing `psql` Output?
@@ -731,7 +731,7 @@ file " ~/_work/pgrx/tests/pgrx-examples/range/tests/pg_regress/regression.diffs"
 above is saved in the file " ~/_work/pgrx/tests/pgrx-examples/range/tests/pg_regress/regression.out".
 ```
 
-And you see the `bad` test immediately failed!  To see how it failed, look at the `./pg_regress/regression.diffs` file:
+And you see the `bad` test immediately failed!  To see how it failed, look at the `./tests/pg_regress/regression.diffs` file:
 
 ```console
 $ diff -U3  ~/_work/pgrx/tests/pgrx-examples/range/tests/pg_regress/expected/bad.out  ~/_work/pgrx/tests/pgrx-examples/range/tests/pg_regress/results/bad.out

cargo-pgrx/src/command/new.rs

@@ -67,8 +67,8 @@ pub(crate) fn create_crate_template(
 fn create_directory_structure(root: PathBuf) -> Result<(), std::io::Error> {
     std::fs::create_dir_all(root.join(".cargo"))?;
     std::fs::create_dir_all(root.join("src").join("bin"))?;
-    std::fs::create_dir_all(root.join("pg_regress").join("expected"))?;
-    std::fs::create_dir_all(root.join("pg_regress").join("sql"))?;
+    std::fs::create_dir_all(root.join("tests").join("pg_regress").join("expected"))?;
+    std::fs::create_dir_all(root.join("tests").join("pg_regress").join("sql"))?;
     std::fs::create_dir_all(root.join("sql"))?;
 
     Ok(())
@@ -141,6 +141,7 @@ fn create_pgrx_embed_rs(mut filename: PathBuf) -> Result<(), std::io::Error> {
 }
 
 fn create_setup_sql(mut filename: PathBuf, name: &str) -> Result<(), std::io::Error> {
+    filename.push("tests");
     filename.push("pg_regress");
     filename.push("sql");
     filename.push("setup.sql");
@@ -150,6 +151,7 @@ fn create_setup_sql(mut filename: PathBuf, name: &str) -> Result<(), std::io::Er
 }
 
 fn create_setup_out(mut filename: PathBuf, name: &str) -> Result<(), std::io::Error> {
+    filename.push("tests");
     filename.push("pg_regress");
     filename.push("expected");
     filename.push("setup.out");

cargo-pgrx/src/templates/gitignore

@@ -4,6 +4,6 @@
 *.iml
 **/*.rs.bk
 Cargo.lock
-pg_regress/results
-pg_regress/regression.diffs
-pg_regress/regression.out
+tests/pg_regress/results
+tests/pg_regress/regression.diffs
+tests/pg_regress/regression.out