Added a --prepend-format option

This lets you, for example, debug registers that cull data from many
different sources, without having to change the basic formatting
string.  You can locate each posting's location with this:

  ledger reg --prepend-format='%-25(filename + ":" + beg_line)'

4 files changed, 57 insertions, 14 deletions

diff --git a/src/output.cc b/src/output.cc
index 2a6f0c20..71ec6d88 100644
--- a/src/output.cc
+++ b/src/output.cc
@@ -40,9 +40,10 @@
 
 namespace ledger {
 
-format_posts::format_posts(report_t&	 _report,
-			   const string& format,
-			   bool		 _print_raw)
+format_posts::format_posts(report_t&		   _report,
+			   const string&	   format,
+			   bool			   _print_raw,
+			   const optional<string>& _prepend_format)
   : report(_report), last_xact(NULL), last_post(NULL),
     print_raw(_print_raw)
 {
@@ -65,6 +66,9 @@ format_posts::format_posts(report_t&	 _report,
     first_line_format.parse_format(format);
     next_lines_format.parse_format(format);
   }
+
+  if (_prepend_format)
+    prepend_format.parse_format(*_prepend_format);
 }
 
 void format_posts::flush()
@@ -95,6 +99,10 @@ void format_posts::operator()(post_t& post)
   else if (! post.has_xdata() ||
 	   ! post.xdata().has_flags(POST_EXT_DISPLAYED)) {
     bind_scope_t bound_scope(report, post);
+
+    if (prepend_format)
+      out << prepend_format(bound_scope);
+
     if (last_xact != post.xact) {
       if (last_xact) {
 	bind_scope_t xact_scope(report, *last_xact);
@@ -115,8 +123,9 @@ void format_posts::operator()(post_t& post)
   }
 }
 
-format_accounts::format_accounts(report_t&     _report,
-				 const string& format)
+format_accounts::format_accounts(report_t&		 _report,
+				 const string&		 format,
+				 const optional<string>& _prepend_format)
   : report(_report), disp_pred()
 {
   TRACE_CTOR(format_accounts, "report&, const string&");
@@ -136,6 +145,9 @@ format_accounts::format_accounts(report_t&     _report,
     account_line_format.parse_format(format);
     total_line_format.parse_format(format, account_line_format);
   }
+
+  if (_prepend_format)
+    prepend_format.parse_format(*_prepend_format);
 }
 
 std::size_t format_accounts::post_account(account_t& account, const bool flat)
@@ -150,6 +162,11 @@ std::size_t format_accounts::post_account(account_t& account, const bool flat)
     account.xdata().add_flags(ACCOUNT_EXT_DISPLAYED);
 
     bind_scope_t bound_scope(report, account);
+
+    if (prepend_format)
+      static_cast<std::ostream&>(report.output_stream)
+	<< prepend_format(bound_scope);
+
     static_cast<std::ostream&>(report.output_stream)
       << account_line_format(bound_scope);
 
@@ -217,6 +234,11 @@ void format_accounts::flush()
       ! report.HANDLED(no_total) && ! report.HANDLED(percent)) {
     bind_scope_t bound_scope(report, *report.session.journal->master);
     out << separator_format(bound_scope);
+
+    if (prepend_format)
+      static_cast<std::ostream&>(report.output_stream)
+	<< prepend_format(bound_scope);
+
     out << total_line_format(bound_scope);
   }
 
diff --git a/src/output.h b/src/output.h
index fedd08ff..778a9335 100644
--- a/src/output.h
+++ b/src/output.h
@@ -60,13 +60,15 @@ protected:
   format_t  first_line_format;
   format_t  next_lines_format;
   format_t  between_format;
+  format_t  prepend_format;
   xact_t *  last_xact;
   post_t *  last_post;
   bool      print_raw;
 
 public:
   format_posts(report_t& _report, const string& format,
-	       bool _print_raw = false);
+	       bool _print_raw = false,
+	       const optional<string>& _prepend_format = none);
   virtual ~format_posts() {
     TRACE_DTOR(format_posts);
   }
@@ -82,12 +84,14 @@ protected:
   format_t    account_line_format;
   format_t    total_line_format;
   format_t    separator_format;
+  format_t    prepend_format;
   predicate_t disp_pred;
 
   std::list<account_t *> posted_accounts;
 
 public:
-  format_accounts(report_t& _report, const string& _format);
+  format_accounts(report_t& _report, const string& _format,
+		  const optional<string>& _prepend_format = none);
   virtual ~format_accounts() {
     TRACE_DTOR(format_accounts);
   }
diff --git a/src/report.cc b/src/report.cc
index 4e9cfe89..4d1a9700 100644
--- a/src/report.cc
+++ b/src/report.cc
@@ -631,6 +631,7 @@ option_t<report_t> * report_t::lookup_option(const char * p)
     else OPT(pricesdb_format_);
     else OPT(print_format_);
     else OPT(payee_width_);
+    else OPT(prepend_format_);
     break;
   case 'q':
     OPT(quantity);
@@ -854,7 +855,8 @@ expr_t::ptr_op_t report_t::lookup(const symbol_t::kind_t kind,
       if (*(p + 1) == '\0' || is_eq(p, "bal") || is_eq(p, "balance")) {
 	return expr_t::op_t::wrap_functor
 	  (reporter<account_t, acct_handler_ptr, &report_t::accounts_report>
-	   (new format_accounts(*this, report_format(HANDLER(balance_format_))),
+	   (new format_accounts(*this, report_format(HANDLER(balance_format_)),
+				maybe_format(HANDLER(prepend_format_))),
 	    *this, "#balance"));
       }
       else if (is_eq(p, "budget")) {
@@ -866,7 +868,8 @@ expr_t::ptr_op_t report_t::lookup(const symbol_t::kind_t kind,
 
 	return expr_t::op_t::wrap_functor
 	  (reporter<account_t, acct_handler_ptr, &report_t::accounts_report>
-	   (new format_accounts(*this, report_format(HANDLER(budget_format_))),
+	   (new format_accounts(*this, report_format(HANDLER(budget_format_)),
+				maybe_format(HANDLER(prepend_format_))),
 	    *this, "#budget"));
       }
       break;
@@ -875,7 +878,8 @@ expr_t::ptr_op_t report_t::lookup(const symbol_t::kind_t kind,
       if (is_eq(p, "csv")) {
 	return WRAP_FUNCTOR
 	  (reporter<>
-	   (new format_posts(*this, report_format(HANDLER(csv_format_))),
+	   (new format_posts(*this, report_format(HANDLER(csv_format_)),
+			     maybe_format(HANDLER(prepend_format_))),
 	    *this, "#csv"));
       }
       else if (is_eq(p, "cleared")) {
@@ -884,7 +888,8 @@ expr_t::ptr_op_t report_t::lookup(const symbol_t::kind_t kind,
 
 	return expr_t::op_t::wrap_functor
 	  (reporter<account_t, acct_handler_ptr, &report_t::accounts_report>
-	   (new format_accounts(*this, report_format(HANDLER(cleared_format_))),
+	   (new format_accounts(*this, report_format(HANDLER(cleared_format_)),
+				maybe_format(HANDLER(prepend_format_))),
 	    *this, "#cleared"));
       }
       break;
@@ -913,12 +918,14 @@ expr_t::ptr_op_t report_t::lookup(const symbol_t::kind_t kind,
       else if (is_eq(p, "prices"))
 	return expr_t::op_t::wrap_functor
 	  (reporter<post_t, post_handler_ptr, &report_t::commodities_report>
-	   (new format_posts(*this, report_format(HANDLER(prices_format_))),
+	   (new format_posts(*this, report_format(HANDLER(prices_format_)),
+			     maybe_format(HANDLER(prepend_format_))),
 	    *this, "#prices"));
       else if (is_eq(p, "pricesdb"))
 	return expr_t::op_t::wrap_functor
 	  (reporter<post_t, post_handler_ptr, &report_t::commodities_report>
-	   (new format_posts(*this, report_format(HANDLER(pricesdb_format_))),
+	   (new format_posts(*this, report_format(HANDLER(pricesdb_format_)),
+			     maybe_format(HANDLER(prepend_format_))),
 	    *this, "#pricesdb"));
       break;
 
@@ -926,7 +933,8 @@ expr_t::ptr_op_t report_t::lookup(const symbol_t::kind_t kind,
       if (*(p + 1) == '\0' || is_eq(p, "reg") || is_eq(p, "register"))
 	return WRAP_FUNCTOR
 	  (reporter<>
-	   (new format_posts(*this, report_format(HANDLER(register_format_))),
+	   (new format_posts(*this, report_format(HANDLER(register_format_)),
+			     false, maybe_format(HANDLER(prepend_format_))),
 	    *this, "#register"));
       else if (is_eq(p, "reload"))
 	return MAKE_FUNCTOR(report_t::reload_command);
diff --git a/src/report.h b/src/report.h
index 02fd2c8d..3afb0107 100644
--- a/src/report.h
+++ b/src/report.h
@@ -172,6 +172,12 @@ public:
     return option.str();
   }
 
+  optional<string> maybe_format(option_t<report_t>& option) {
+    if (option)
+      return option.str();
+    return none;
+  }
+
   value_t reload_command(call_scope_t&);
   value_t echo_command(call_scope_t& scope);
 
@@ -252,6 +258,7 @@ public:
     HANDLER(period_).report(out);
     HANDLER(plot_amount_format_).report(out);
     HANDLER(plot_total_format_).report(out);
+    HANDLER(prepend_format_).report(out);
     HANDLER(price).report(out);
     HANDLER(prices_format_).report(out);
     HANDLER(pricesdb_format_).report(out);
@@ -693,6 +700,8 @@ public:
 	 "%(format_date(date, \"%Y-%m-%d\")) %(quantity(scrub(display_total)))\n");
     });
 
+  OPTION(report_t, prepend_format_);
+
   OPTION_(report_t, price, DO() { // -I
       parent->HANDLER(display_amount_)
 	.set_expr(string("--price"), "price(amount_expr)");