only import site once when running interactively in a context, simplify getting the prompt

Author: timfel

graalpython/com.oracle.graal.python.shell/src/com/oracle/graal/python/shell/GraalPythonMain.java

@@ -59,8 +59,6 @@ public static void main(String[] args) {
 
     private static final String LANGUAGE_ID = "python";
     private static final Source QUIT_EOF = Source.newBuilder(LANGUAGE_ID, "import site\nexit()", "<exit-on-eof>").internal(true).buildLiteral();
-    private static final Source GET_PROMPT = Source.newBuilder(LANGUAGE_ID, "import sys\nsys.ps1", "<prompt>").internal(true).buildLiteral();
-    private static final Source GET_CONTINUE_PROMPT = Source.newBuilder(LANGUAGE_ID, "import sys\nsys.ps2", "<continue-prompt>").internal(true).buildLiteral();
 
     private ArrayList<String> programArgs = null;
     private String commandString = null;
@@ -519,10 +517,12 @@ public int readEvalPrint(Context context, ConsoleHandler consoleHandler) {
         int lastStatus = 0;
         try {
             setupReadline(context, consoleHandler);
+            Value sys = context.eval(Source.create(getLanguageId(), "import sys; sys"));
+            context.eval(Source.create(getLanguageId(), "del sys\ndel site\ndel readline"));
 
             while (true) { // processing inputs
                 boolean doEcho = doEcho(context);
-                consoleHandler.setPrompt(doEcho ? getPrompt(context) : null);
+                consoleHandler.setPrompt(doEcho ? sys.getMember("ps1").asString() : null);
 
                 try {
                     String input = consoleHandler.readLine();
@@ -542,7 +542,7 @@ public int readEvalPrint(Context context, ConsoleHandler consoleHandler) {
                             context.eval(Source.newBuilder(getLanguageId(), sb.toString(), "<stdin>").interactive(true).buildLiteral());
                         } catch (PolyglotException e) {
                             if (continuePrompt == null) {
-                                continuePrompt = doEcho ? getContinuePrompt(context) : null;
+                                continuePrompt = doEcho ? sys.getMember("ps2").asString() : null;
                             }
                             if (e.isIncompleteSource()) {
                                 // read another line of input
@@ -597,7 +597,7 @@ private void setupReadline(Context context, ConsoleHandler consoleHandler) {
         context.eval(Source.newBuilder(getLanguageId(), "None", "setup-interactive").interactive(true).buildLiteral());
         // Then we can get the readline module and see if any completers were registered and use its
         // history feature
-        final Value readline = context.eval(Source.newBuilder(getLanguageId(), "import readline; readline", "setup-interactive").buildLiteral());
+        final Value readline = context.eval(Source.create(getLanguageId(), "import readline; readline"));
         final Value completer = readline.getMember("get_completer").execute();
         final Value shouldRecord = readline.getMember("get_auto_history");
         final Value addHistory = readline.getMember("add_history");
@@ -640,26 +640,4 @@ private static final class ExitException extends RuntimeException {
     private static boolean doEcho(@SuppressWarnings("unused") Context context) {
         return true;
     }
-
-    private static String getPrompt(Context context) {
-        try {
-            return context.eval(GET_PROMPT).asString();
-        } catch (PolyglotException e) {
-            if (e.isExit()) {
-                throw new ExitException(e.getExitStatus());
-            }
-            throw new RuntimeException("error while retrieving prompt", e);
-        }
-    }
-
-    private static String getContinuePrompt(Context context) {
-        try {
-            return context.eval(GET_CONTINUE_PROMPT).asString();
-        } catch (PolyglotException e) {
-            if (e.isExit()) {
-                throw new ExitException(e.getExitStatus());
-            }
-            throw new RuntimeException("error while retrieving continue prompt", e);
-        }
-    }
 }

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/PythonLanguage.java

@@ -38,6 +38,7 @@
 import com.oracle.graal.python.builtins.objects.PNone;
 import com.oracle.graal.python.builtins.objects.PythonAbstractObject;
 import com.oracle.graal.python.builtins.objects.code.PCode;
+import com.oracle.graal.python.builtins.objects.common.HashingStorage;
 import com.oracle.graal.python.builtins.objects.function.PArguments;
 import com.oracle.graal.python.builtins.objects.function.PBuiltinFunction;
 import com.oracle.graal.python.builtins.objects.function.PKeyword;
@@ -242,10 +243,14 @@ protected CallTarget parse(ParsingRequest request) throws Exception {
         }
     }
 
-    static final String interactiveStartup = "import site\nimport sys\ngetattr(sys, '__interactivehook__', lambda: None)()";
-
     private void runInteractiveStartup(PythonCore pythonCore) {
-        Truffle.getRuntime().createCallTarget(new TopLevelExceptionHandler(this, doParse(pythonCore, Source.newBuilder(ID, interactiveStartup, "<site import>").build()))).call();
+        PythonContext context = pythonCore.getContext();
+        HashingStorage sysModules = context.getImportedModules().getDictStorage();
+        String siteModuleName = "site";
+        if (!sysModules.hasKey(siteModuleName, HashingStorage.getSlowPathEquivalence(siteModuleName))) {
+            Source src = Source.newBuilder(ID, "import site\nimport sys\ngetattr(sys, '__interactivehook__', lambda: None)()\n", "<site import>").build();
+            Truffle.getRuntime().createCallTarget(new TopLevelExceptionHandler(this, doParse(pythonCore, src))).call();
+        }
     }
 
     private RootNode doParse(PythonCore pythonCore, Source source) {