Add flags to configure basic format styles.

Fixes chipsalliance#1046

Signed-off-by: Henner Zeller <[email protected]>

common/formatting/BUILD

@@ -63,6 +63,17 @@ cc_library(
     ],
 )
 
+cc_library(
+    name = "basic_format_style_init",
+    srcs = ["basic_format_style_init.cc"],
+    hdrs = ["basic_format_style_init.h"],
+    deps = [
+        ":basic_format_style",
+        "@com_google_absl//absl/flags:flag",
+        "@com_google_absl//absl/strings",
+    ],
+)
+
 cc_test(
     name = "basic_format_style_test",
     srcs = ["basic_format_style_test.cc"],

common/formatting/basic_format_style.h

@@ -42,6 +42,8 @@ struct BasicFormatStyle {
 
   // Penalty added to solution for each introduced line break.
   int line_break_penalty = 2;
+
+  // -- Note: when adding new fields, add them in basic_format_style_init.cc
 };
 
 // Control how a section of code is indented.

common/formatting/basic_format_style_init.cc

@@ -0,0 +1,52 @@
+// Copyright 2017-2021 The Verible Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "common/formatting/basic_format_style_init.h"
+
+#include "absl/flags/flag.h"
+
+ABSL_FLAG(int, indentation_spaces, 2,
+          "Each indentation level adds this many spaces.");
+
+ABSL_FLAG(int, wrap_spaces, 4,
+          "Each wrap level adds this many spaces.  This applies when the first "
+          "element after an open-group section is wrapped.  Otherwise, the "
+          "indentation level is set to the column position of the open-group "
+          "operator.");
+
+ABSL_FLAG(int, column_limit, 100,
+          "Target line length limit to stay under when formatting.");
+
+ABSL_FLAG(int, over_column_limit_penalty, 100,
+          "For penalty minimization, this represents the baseline penalty "
+          "value of exceeding the column limit.  Additional penalty of 1 is "
+          "incurred for each character over this limit");
+
+ABSL_FLAG(int, line_break_penalty, 2,
+          "Penalty added to solution for each introduced line break.");
+
+namespace verible {
+void InitializeFromFlags(BasicFormatStyle *style) {
+#define STYLE_FROM_FLAG(name) style->name = absl::GetFlag(FLAGS_##name)
+
+  // Simply in the sequence as declared in struct BasicFormatStyle
+  STYLE_FROM_FLAG(indentation_spaces);
+  STYLE_FROM_FLAG(wrap_spaces);
+  STYLE_FROM_FLAG(column_limit);
+  STYLE_FROM_FLAG(over_column_limit_penalty);
+  STYLE_FROM_FLAG(line_break_penalty);
+
+#undef STYLE_FROM_FLAG
+}
+}  // namespace verible

common/formatting/basic_format_style_init.h

@@ -0,0 +1,29 @@
+// Copyright 2017-2021 The Verible Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef VERIBLE_COMMON_FORMATTING_BASIC_FORMAT_STYLE_INIT_H_
+#define VERIBLE_COMMON_FORMATTING_BASIC_FORMAT_STYLE_INIT_H_
+
+#include "common/formatting/basic_format_style.h"
+
+namespace verible {
+
+// Initialize format style from flags.
+void InitializeFromFlags(BasicFormatStyle *style);
+
+// TODO: initialize from configuration file.
+// https://github.com/chipsalliance/verible/issues/898
+// Possibly using common/text/config_utils.h
+}  // namespace verible
+#endif  // VERIBLE_COMMON_FORMATTING_BASIC_FORMAT_STYLE_INIT_H_

verilog/formatting/BUILD

@@ -244,6 +244,7 @@ cc_library(
     hdrs = ["format_style_init.h"],
     deps = [
         ":format_style",
+        "//common/formatting:basic_format_style_init",
         "@com_google_absl//absl/flags:flag",
         "@com_google_absl//absl/strings",
     ],

verilog/formatting/format_style_init.cc

@@ -1,4 +1,4 @@
-// Copyright 2017-2020 The Verible Authors.
+// Copyright 2017-2021 The Verible Authors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -15,6 +15,7 @@
 #include "verilog/formatting/format_style_init.h"
 
 #include "absl/flags/flag.h"
+#include "common/formatting/basic_format_style_init.h"
 
 using verible::AlignmentPolicy;
 using verible::IndentationStyle;
@@ -105,6 +106,8 @@ ABSL_RETIRED_FLAG(
 namespace verilog {
 namespace formatter {
 void InitializeFromFlags(FormatStyle *style) {
+  verible::InitializeFromFlags(style);  // Initialize BasicFormatStyle
+
 #define STYLE_FROM_FLAG(name) style->name = absl::GetFlag(FLAGS_##name)
 
   // Simply in the sequence as declared in struct FormatStyle

verilog/formatting/format_style_init.h

@@ -1,4 +1,4 @@
-// Copyright 2017-2020 The Verible Authors.
+// Copyright 2017-2021 The Verible Authors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.

verilog/tools/formatter/README.md

@@ -13,6 +13,21 @@ get a full set of avilable flags using the `--helpfull` flag.
 usage: verible-verilog-format [options] <file> [<file...>]
 To pipe from stdin, use '-' as <file>.
 
+  Flags from common/formatting/basic_format_style_init.cc:
+    --column_limit (Target line length limit to stay under when formatting.);
+      default: 100;
+    --indentation_spaces (Each indentation level adds this many spaces.);
+      default: 2;
+    --line_break_penalty (Penalty added to solution for each introduced line
+      break.); default: 2;
+    --over_column_limit_penalty (For penalty minimization, this represents the
+      baseline penalty value of exceeding the column limit. Additional penalty
+      of 1 is incurred for each character over this limit); default: 100;
+    --wrap_spaces (Each wrap level adds this many spaces. This applies when the
+      first element after an open-group section is wrapped. Otherwise, the
+      indentation level is set to the column position of the open-group
+      operator.); default: 4;
+
   Flags from verilog/formatting/format_style_init.cc:
     --assignment_statement_alignment (Format various assignments:
       {align,flush-left,preserve,infer}); default: infer;