From d71a219019f099e6c8a3be18e5ace3f06faaeded Mon Sep 17 00:00:00 2001
From: Christophe Rhodes <csr21@cantab.net>
Date: Fri, 8 Oct 2010 12:05:49 +0100
Subject: [PATCH] capture output from evaluating swank requests

This fixes bug #1.  It is somewhat on the risky side given that there
are current known protocol problems in the presence of non-ASCII
encodings, but it does make working in the slime repl much more
pleasant.
---
 BUGS.org |  2 +-
 swank.R  | 24 ++++++++++++++++++------
 2 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/BUGS.org b/BUGS.org
index dfde868..2181580 100644
--- a/BUGS.org
+++ b/BUGS.org
@@ -3,7 +3,7 @@
 #+AUTHOR: Christophe Rhodes
 #+EMAIL: csr21@cantab.net
 #+OPTIONS: H:0 toc:nil
-* OPEN #1 printed output not redirected to slime repl                 :MINOR:
+* RESOLVED #1 printed output not redirected to slime repl       :MINOR:FIXED:
   The output from functions performing printing is sent to the
   standard output of the process running =swank()=, not to an emacs
   stream.
diff --git a/swank.R b/swank.R
index fa22d64..0384004 100644
--- a/swank.R
+++ b/swank.R
@@ -42,7 +42,6 @@ mainLoop <- function(io) {
 }
 
 dispatch <- function(slimeConnection, event, sldbState=NULL) {
-  str(event)
   kind <- event[[1]]
   if(kind == quote(`:emacs-rex`)) {
     do.call("emacsRex", c(list(slimeConnection), list(sldbState), event[-1]))
@@ -51,12 +50,10 @@ dispatch <- function(slimeConnection, event, sldbState=NULL) {
 
 sendToEmacs <- function(slimeConnection, obj) {
   io <- slimeConnection$io
-  str(obj)
   payload <- writeSexpToString(obj)
   writeChar(sprintf("%06x", nchar(payload)), io, eos=NULL)
   writeChar(payload, io, eos=NULL)
   flush(io)
-  cat(sprintf("%06x", nchar(payload)), payload, sep="")
 }
 
 callify <- function(form) {
@@ -81,15 +78,30 @@ callify <- function(form) {
 emacsRex <- function(slimeConnection, sldbState, form, pkg, thread, id, level=0) {
   ok <- FALSE
   value <- NULL
+  conn <- textConnection(NULL, open="w")
+  condition <- NULL
   tryCatch({
     withCallingHandlers({
       call <- callify(form)
-      value <- eval(call)
+      capture.output(value <- eval(call), file=conn)
+      string <- paste(textConnectionValue(conn), sep="", collapse="\n")
+      if(nchar(string) > 0) {
+        sendToEmacs(slimeConnection, list(quote(`:write-string`), string))
+        sendToEmacs(slimeConnection, list(quote(`:write-string`), "\n"))
+      }
+      close(conn)
       ok <- TRUE
     }, error=function(c) {
+      condition <<- c
+      string <- paste(textConnectionValue(conn), sep="", collapse="\n")
+      if(nchar(string) > 0) {
+        sendToEmacs(slimeConnection, list(quote(`:write-string`), string))
+        sendToEmacs(slimeConnection, list(quote(`:write-string`), "\n"))
+      }
+      close(conn)
       newSldbState <- makeSldbState(c, if(is.null(sldbState)) 0 else sldbState$level+1, id)
       withRestarts(sldbLoop(slimeConnection, newSldbState, id), abort=paste("return to sldb level", newSldbState$level)) })},
-    finally=sendToEmacs(slimeConnection, list(quote(`:return`), if(ok) list(quote(`:ok`), value) else list(quote(`:abort`)), id)))
+    finally=sendToEmacs(slimeConnection, list(quote(`:return`), if(ok) list(quote(`:ok`), value) else list(quote(`:abort`), as.character(condition)), id)))
 }
 
 makeSldbState <- function(condition, level, id) {
@@ -266,7 +278,7 @@ printToString <- function(val) {
   for(contrib in contribs) {
     filename <- sprintf("%s.R", as.character(contrib))
     if(file.exists(filename)) {
-      source(filename, verbose=TRUE)
+      source(filename)
     }
   }
   list()
-- 
2.39.5