Trac #32933: Put SAGE_ROOT/src/bin in PATH only when invoked by SAGE_…

…ROOT/sage or sage-build-env

Only when invoked as `SAGE_ROOT/sage` or `SAGE_ROOT/src/bin/sage`, then
`$SAGE_ROOT/src/bin` should be put in the front of `PATH`.

When the installed `sage` script, `SAGE_VENV/bin/sage`, is invoked
directly, it should not put `$SAGE_ROOT/src/bin` on the `PATH`.

URL: https://trac.sagemath.org/32933
Reported by: mkoeppe
Ticket author(s): Matthias Koeppe
Reviewer(s): Kwankyu Lee

src/bin/sage

@@ -298,6 +298,12 @@ if [ -f "${SELF}-env" ]; then
     fi
 fi
 
+if [ -f "${SELF}-src-env-config.in" ]; then
+    # The sage script is being run out of SAGE_ROOT/src/bin.
+    # In this case, put this directory in the front of the PATH.
+    export PATH="$SAGE_SRC/bin:$PATH"
+fi
+
 if [ -z "$DOT_SAGE" ]; then
     export DOT_SAGE="$HOME/.sage"
 fi

src/bin/sage-env

@@ -295,9 +295,6 @@ fi
 if [ -n "$SAGE_VENV" ]; then
     export PATH="$SAGE_VENV/bin:$PATH"
 fi
-if [ -n "$SAGE_SRC" ]; then
-    export PATH="$SAGE_SRC/bin:$PATH"
-fi
 if [ -n "$SAGE_ROOT" ]; then
     export PATH="$SAGE_ROOT/build/bin:$PATH"
 fi