standard library: bring the tests into the main CI (#8525)

Should close one of the tasks in #8450.

# Description
> **Note**
> in order of appearance in the global diff

- 1b7497c419 adds the `std-tests` job to
the CI which
  1. installs `nushell` in the runner
  2. run the `tests.nu` module
> see `open .github/workflows/ci.yml | get jobs.std-tests | to yaml`

-
[`ec85b6fd`..`9c122115`](ec85b6fd3fc004cd94e3fada5c8e5fe2714fd629..9c12211564ca8ee90ed65ae45776dccb8f8e4ef1)
is where all the magic happens => see below
- 🧪 799c7eb7fd introduces some
bugs and failing test to see how the CI behaves => see how the [tests
failed](https://github.com/nushell/nushell/actions/runs/4460098237/jobs/7833018256)
as expected ❌
- 🧪 and c3de1fafb5 reverts the
failing tests, i.e. the previous commit, leaving a standard library
whose tests all pass 🎉 => see the [tests
passing](https://github.com/nushell/nushell/actions/runs/4460153434/jobs/7833110719?pr=8525#step:5:1)
now ✔️

## the changes to the runner
> see
[`ec85b6fd`..`9c122115`](ec85b6fd3fc004cd94e3fada5c8e5fe2714fd629..9c12211564ca8ee90ed65ae45776dccb8f8e4ef1)

the issue with the previous runner was the following: the clever trick
of using `nu -c "use ...; test"` did print the errors when occuring but
they did not capture the true "failure", i.e. in all cases the
`$env.LAST_EXIT_CODE` was set to `0`, never stopping the CI when a test
failed 🤔

i first tried to `try` / `catch` the error in
ec85b6fd3f which kinda worked but only
throw a single error, the first one

i thought it was not the best and started thinking about a solution to
have a complete report of all failing tests, at once, to avoid running
the CI multiple times!

the easiest solution i found was the one i implemented in
9c12211564
> **Warning**
> this changes the structure of the runner quite a bit, but the `for`
loops where annoying to manipulate structured data and allow the runner
to draw a complete report...

now the runner does the following
- compute the list of all available tests in a table with the `file`,
`module` and `name` columns (first part of the pipe until `flatten` and
`rename`)
- run the tests one by one computing the new `pass` column
  - with a `log info`
- captures the failing ones => puts `true` in `pass` if the test passes,
`false` otherwise
- if at least one test has failed, throw a single error with the list of
failing tests

### hope you'll like it 😌 

# User-Facing Changes
```
$nothing
```

# Tests + Formatting
the standard tests now return a true error that will stop the CI

# After Submitting
```
$nothing
```

.github/workflows/ci.yml

@@ -82,9 +82,9 @@ jobs:
       - name: Tests
         run: cargo test --workspace --profile ci --exclude nu_plugin_* ${{ matrix.flags }}
 
-  python-virtualenv:
+  std-lib-and-python-virtualenv:
     env:
-      NUSHELL_CARGO_TARGET: ci
+      NU_LOG_LEVEL: DEBUG 
 
     strategy:
       fail-fast: true
@@ -104,7 +104,19 @@ jobs:
         uses: actions-rust-lang/setup-rust-toolchain@v1.4.4
 
       - name: Install Nushell
-        run: cargo install --locked --path=. --profile ci --no-default-features
+        # prior to [*standard library: bring the tests into the main CI*](#8525)
+        # there was a `--profile ci` here in the `cargo install`, as well as
+        # `NUSHELL_CARGO_TARGET: ci` in the prelude above.
+        #
+        # this caused a "stackoverflow" error in the CI on windows,
+        # see [this failing job](https://github.com/nushell/nushell/actions/runs/4512034615/jobs/7944945590)
+        #
+        # the CI profile has been removed in 00b820de9021227d1910a9ea388297ee7aee308e
+        # as part of #8525.
+        run: cargo install --path . --locked --no-default-features
+
+      - name: Standard library tests
+        run: nu crates/nu-utils/standard_library/tests.nu
 
       - name: Setup Python
         uses: actions/setup-python@v4

crates/nu-utils/standard_library/tests.nu

@@ -1,31 +1,23 @@
 use std.nu *
 
-def collect-modules [
-    path: path,
-    module?: string
-] {
-    let tests_path = ($path | default $env.FILE_PWD)
-    let module_search = ($module | default "test_*")
-    (ls ($tests_path | path join $"**/($module_search).nu") -f | get name)    
-}
+# show a test record in a pretty way
+#
+# `$in` must be a `record<file: string, module: string, name: string, pass: bool>`.
+#
+# the output would be like
+# - "<indentation> x <module> <test>" all in red if failed
+# - "<indentation>   <module> <test>" all in green if passed
+def show-pretty-test [indent: int = 4] {
+    let test = $in
 
-def collect-commands [
-    test_file: string,
-    module_name: string,
-    command?: string
-] {
-    let commands = (
-        nu -c $'use ($test_file) *; $nu.scope.commands | select name module_name | to nuon'
-        | from nuon
-        | where module_name == $module_name
-        | where ($it.name | str starts-with "test_")
-        | get name
-    )
-    if $command == null {
-        $commands
-    } else {
-        $commands | where $it == $command
-    }
+    [
+        (" " * $indent)
+        (if $test.pass { ansi green } else { ansi red})
+        (if $test.pass { " " } else { char failed})
+        " "
+        $"($test.module) ($test.name)"
+        (ansi reset)
+    ] | str join
 }
 
 # Test executor
@@ -35,22 +27,61 @@ def main [
     --path: path, # Path to look for tests. Default: directory of this file.
     --module: string, # Module to run tests. Default: all test modules found.
     --command: string, # Test command to run. Default: all test command found in the files.
-    --list, # Do not run any tests, just list them (dry run)
+    --list, # list the selected tests without running them.
 ] {
-    let dry_run = ($list | default false)
-    for test_file in (collect-modules $path $module) {
-        let $module_name = ($test_file | path parse).stem
-
-        log info $"Run tests in ($module_name)"
-        let tests = (collect-commands $test_file $module_name $command)
-
-        for test_case in $tests {
-            log debug $"Run test ($module_name) ($test_case)"
-            if $dry_run {
-                continue
-            }
-
-            nu -c $'use ($test_file) ($test_case); ($test_case)'
+    let tests = (
+        ls ($path | default $env.FILE_PWD | path join "test_*.nu")
+        | each {|row| {file: $row.name name: ($row.name | path parse | get stem)}}
+        | upsert test {|module|
+            nu -c $'use ($module.file) *; $nu.scope.commands | select name module_name | to nuon'
+            | from nuon
+            | where module_name == $module.name
+            | where ($it.name | str starts-with "test_")
+            | get name
         }
+        | flatten
+        | rename file module name
+    )
+
+    let tests_to_run = (if not ($command | is-empty) {
+        $tests | where name == $command
+    } else if not ($module | is-empty) {
+        $tests | where module == $module
+    } else {
+        $tests
+    })
+
+    if $list {
+        return ($tests_to_run | select module name file)
+    }
+
+    let tests = (
+        $tests_to_run
+        | group-by module
+        | transpose name tests
+        | each {|module|
+            log info $"Running tests in ($module.name)"
+            $module.tests | each {|test|
+                log debug $"Running test ($test.name)"
+                let did_pass = (try {
+                    nu -c $'use ($test.file) ($test.name); ($test.name)'
+                    true
+                } catch { false })
+
+                $test | merge ({pass: $did_pass})
+            }
+        }
+        | flatten
+    )
+
+    if not ($tests | where not pass | is-empty) {
+        let text = ([
+            $"(ansi purple)some tests did not pass (char lparen)see complete errors above(char rparen):(ansi reset)"
+            ""
+            ($tests | each {|test| ($test | show-pretty-test 4)} | str join "\n")
+            ""
+        ] | str join "\n")
+
+        error make --unspanned { msg: $text }
     }
 }