Fix #20, fix #21, fix #22 (#23)

* Address #20 (tested on macOS)

* Address #21 (tested on macOS)

* Address #22 (tested on macOS)

README.md

@@ -53,10 +53,16 @@ you select and copy them from this page and paste them into the command line.
 5. Run the installation script:
    - Windows: `.\install.ps1`
    - Unix: `./install.sh`
-6. Once the script has finished, remove it:
-   - Windows: `rm install.ps1`
-   - Unix: `rm install.sh`
-7. Close the terminal.
+6. Close the terminal.
+
+You will have the following files in your M269 folder:
+- the installation script in `install.ps1` or `install.sh`
+- the list of M269 software in `requirements.txt`
+- the style changes to Jupyter notebooks in `custom.css`
+- the code checker (see Section 4 below) in `allowed.py` and `m269.json`
+
+We recommend you do _not_ remove these files, so that you can re-install
+the software, if needed.
 
 ## 3 Usage
 
@@ -160,6 +166,19 @@ If you want to remove the M269 styling of notebooks:
 2. Delete all lines from the comment marking the start of M269-23J styling up to the comment ending it.
 3. Save the file and close the editor.
 
+## 6 Re-installing
+
+If you haven't removed the installation files from your M269 folder,
+you can re-install the software after uninstalling it,
+e.g. to work again on your M269 notebooks. Do as follows:
+
+1. Open a PowerShell (Windows) or a terminal (Unix).
+2. Go to your M269 folder by entering `cd <M269 folder path>`, e.g. `cd ~/OU/m269-23j`.
+3. Run the installation script with `.\install.ps1 .` (Windows) or `./install.sh .` (Unix).
+   Note the extra space and period after the command, compared to step 5 in Section 2.
+   (During re-installation, ignore messages saying that a file can't be copied onto itself.)
+4. Close the terminal.
+
 ## Licence
 
 The code and text in this repository are

install.ps1

@@ -21,16 +21,20 @@ $VENV = "$HOME\venvs\$COURSE"
 function is-m269-folder {
     param($path)
     if (-not (Test-Path $path -PathType Container)) {
+        $folder = $path
         $msg="doesn't exist or isn't a folder"
     }
-    elseif (-not ($path -match "[Mm]269-23[Jj]$")) {
-        $msg="must be named m269-23j or M269-23J"
-    }
-    else
-    {
-        return
+    else {
+        $folder = Convert-Path $path
+        if (-not ((Get-Item $folder).Name -match "[Mm]269-23[Jj]")) {
+            $msg="must be named m269-23j or M269-23J"
+        }
+        else
+        {
+            return
+        }
     }
-    Write-Host "$path can't be your M269 folder: it $msg."; Write-Host $DOC
+    Write-Host "$folder can't be your M269 folder: it $msg."; Write-Host $DOC
     exit
 }
 
@@ -51,9 +55,8 @@ if ($args.Length -gt 1) {
     mkdir $HOME\.jupyter\custom -ErrorAction SilentlyContinue
     if (Test-Path $HOME\.jupyter\custom\custom.css) {
         Add-Content -Path $HOME\.jupyter\custom\custom.css -Value (Get-Content custom.css)
-        Remove-Item custom.css
     } else {
-        Move-Item -Path custom.css -Destination $HOME\.jupyter\custom
+        Copy-Item -Path custom.css -Destination $HOME\.jupyter\custom
     }
 } else {
     is-m269-folder $args[0]
@@ -84,9 +87,6 @@ Write-Host "Downloading and installing Python packages... (this will take long)"
 python -m pip install --upgrade pip
 python -m pip install -r requirements.txt
 deactivate
-if ($args.Length -eq 0) {
-    Remove-Item requirements.txt
-}
 
 Write-Host "Adding shortcut commands to the PowerShell config file..."
 
@@ -98,7 +98,7 @@ function m269-23j {
     $VENV\Scripts\Activate.ps1
 }
 function nb {
-    Start-process -NoNewWindow jupyter -ArgumentList "notebook $ESC$FOLDER$ESC"
+    Start-process -NoNewWindow jupyter -ArgumentList "notebook"
 }
 function allowed {
     param(

install.sh

@@ -58,14 +58,18 @@ fi
 is_m269_folder () {
     if [[ ! -d $1 ]]    # single bracket would split path string on spaces
     then
+        folder=$1
         msg="doesn't exist or isn't a folder"
-    elif [[ $(basename "$1") != [Mm]269-23[Jj] ]]
-    then
-        msg="must be named m269-23j or M269-23J"
     else
-        return
+        folder=$(cd "$1"; pwd)
+        if [[ $(basename "$folder") != [Mm]269-23[Jj] ]]
+        then
+            msg="must be named m269-23j or M269-23J"
+        else
+            return
+        fi
     fi
-    echo "$1 can't be your M269 folder: it $msg." ; echo $DOC
+    echo "$folder can't be your M269 folder: it $msg." ; echo $DOC
     exit 1
 }
 
@@ -90,9 +94,8 @@ then
     if [ -f ~/.jupyter/custom/$CSS ]
     then
         cat $CSS >> ~/.jupyter/custom/$CSS
-        rm $CSS
     else
-        mv $CSS ~/.jupyter/custom
+        cp -a $CSS ~/.jupyter/custom
     fi
 else
     is_m269_folder "$1"
@@ -126,17 +129,12 @@ pip install --upgrade pip
 pip install -r $REQS
 pip install pytype==2023.4.27               # install pytype only for Unix
 deactivate
-# if we're in the M269 folder, remove the no longer needed file
-if [ $# -eq 0 ]
-then
-    rm $REQS
-fi
 echo "Software has been installed."
 
 echo "Adding shortcut commands to $shell's startup file..."
 
 M269="cd \"$FOLDER\";source $VENV/bin/activate"
-NB="jupyter notebook \"$FOLDER\"&"
+NB="jupyter notebook &"
 ALLOWED="python3.10 \"$FOLDER/allowed.py\" -c \"$FOLDER/m269.json\""
 
 if [ $shell = "fish" ]