Fix Python Indentation for Verilog Bug

Also add `D1.pytv` Example

Cargo.toml

@@ -3,7 +3,7 @@ name = "pytv"
 description = "Python Templated Verilog"
 repository = "https://github.com/autohdw/pytv"
 authors = ["Teddy van Jerry <me@teddy-van-jerry.org>"]
-version = "0.3.3"
+version = "0.4.0"
 readme = "README.md"
 license = "GPL-3.0-or-later"
 keywords = ["verilog", "python", "template", "generation"]

examples/D1.pytv

@@ -0,0 +1,58 @@
+//! # port enable settings
+//! if_rst = True
+//! if_en  = True
+// Delay by 1 clock
+`timescale 1ns / 1ps
+
+module `OUTPUT_VERILOG_FILE_STEM`#(
+    parameter dwt = 16
+)(
+    op_in, clk
+//! if (if_rst):
+    , rst_n
+//! if (if_en):
+    , en
+//! #
+    , op_out
+);
+
+    input [dwt-1:0] op_in;
+    input clk;
+//! if (if_rst):
+    input rst_n;
+//! if (if_en):
+    input en;
+//! #
+    output reg [dwt-1:0] op_out;
+
+//! if (if_rst and if_en):
+    always @(posedge clk, negedge rst_n) begin
+        if (!rst_n) begin
+            op_out <= 'b0;
+        end  
+        else if (en) begin
+            op_out <= op_in;
+        end
+    end
+//! elif (if_rst and (not if_en)):
+    always @(posedge clk, negedge rst_n) begin
+        if (!rst_n) begin
+            op_out <= 'b0;
+        end 
+        else begin 
+            op_out <= op_in;
+        end
+    end
+//! elif ((not if_rst) and if_en):
+    always @(posedge clk, negedge rst_n) begin
+        if (en) begin
+            op_out <= op_in;
+        end
+    end
+//! else:
+    always @(posedge clk) begin
+        op_out <= op_in;
+    end
+//! #
+
+endmodule

examples/test.pytv

@@ -4,7 +4,8 @@ module `OUTPUT_VERILOG_FILE_STEM`;
 
 Do nothing here!
 //! for i in range(5):
-//!     print("Teddy bear!")
+Teddy Bears!
+//! # <- mark the end of group
 Do nothing here either! { some content }
 //! a = 2
 `1 + 2` and how about here ` a * 2 `

src/convert.rs

@@ -58,20 +58,24 @@ impl Convert {
 
     /// Generates the output file name based on the input file name and configuration.
     fn output_file_name(&self) -> String {
-        self.file_options.output.clone().unwrap_or_else(|| {
-            if self.file_options.output.is_some() {
-                return self.file_options.input.clone();
-            }
-            let mut output = self.file_options.input.clone();
-            // change extension to .v if there is extension
-            let ext = path::Path::new(&output).extension().unwrap_or_default();
-            if ext.is_empty() {
-                output.push_str(".v");
-            } else {
-                output = output.replace(ext.to_str().unwrap(), "v");
-            }
-            output
-        }).replace("\\", "/")
+        self.file_options
+            .output
+            .clone()
+            .unwrap_or_else(|| {
+                if self.file_options.output.is_some() {
+                    return self.file_options.input.clone();
+                }
+                let mut output = self.file_options.input.clone();
+                // change extension to .v if there is extension
+                let ext = path::Path::new(&output).extension().unwrap_or_default();
+                if ext.is_empty() {
+                    output.push_str(".v");
+                } else {
+                    output = output.replace(ext.to_str().unwrap(), "v");
+                }
+                output
+            })
+            .replace("\\", "/")
     }
 
     /// Generates the output Python file name based on the input file name and configuration.
@@ -183,10 +187,10 @@ impl Convert {
     fn process_python_line<W: Write>(
         &self,
         line: &str,
-        py_indent_space: usize,
+        py_indent_prior: usize,
         stream: &mut W,
     ) -> Result<()> {
-        writeln!(stream, "{}", utf8_slice::from(&line, py_indent_space))
+        writeln!(stream, "{}", utf8_slice::from(&line, py_indent_prior))
     }
 
     #[cfg(feature = "macro")]
@@ -214,9 +218,24 @@ impl Convert {
         Ok(())
     }
 
+    fn update_py_indent_space(&self, line: &str, py_indent_space: usize) -> usize {
+        if !line.is_empty() {
+            let re = regex::Regex::new(r":\s*(#|$)").unwrap();
+            line.chars().position(|c| !c.is_whitespace()).unwrap_or(0)
+                + if re.is_match(line) {
+                    self.config.tab_size as usize
+                } else {
+                    0usize
+                }
+        } else {
+            py_indent_space
+        }
+    }
+
     /// Converts the code and writes the converted code to the given stream.
     pub fn convert<W: Write>(&self, mut stream: W) -> Result<(), Box<dyn Error>> {
         let mut first_py_line = false;
+        let mut py_indent_prior = 0usize;
         let mut py_indent_space = 0usize;
         let magic_string_len = 2 + self.config.magic_comment_str.len();
         #[cfg(feature = "inst")]
@@ -248,6 +267,7 @@ impl Convert {
             self.switch_line_type(&mut line_type, line.as_str());
             match line_type {
                 LineType::PythonBlock(true) => {
+                    py_indent_space = self.update_py_indent_space(&line, py_indent_space);
                     #[cfg(feature = "inst")]
                     self.process_python_line(
                         &line,
@@ -263,29 +283,30 @@ impl Convert {
                     let line = utf8_slice::from(line.trim_start(), magic_string_len);
                     if !first_py_line && !line.is_empty() {
                         first_py_line = true;
-                        py_indent_space =
+                        py_indent_prior =
                             line.chars().position(|c| !c.is_whitespace()).unwrap_or(0);
                     }
-                    if !utf8_slice::till(&line, py_indent_space).trim().is_empty() {
+                    if !utf8_slice::till(&line, py_indent_prior).trim().is_empty() {
                         Err(format!(
                             "Python line should start with {} spaces.\nUnexpected line: {}",
-                            py_indent_space, &line
+                            py_indent_prior, &line
                         ))?;
                     }
+                    py_indent_space = self.update_py_indent_space(&line, py_indent_space) - py_indent_prior;
                     #[cfg(feature = "inst")]
                     self.process_python_line(
                         &line,
-                        py_indent_space,
+                        py_indent_prior,
                         &mut stream,
                         &mut within_inst,
                         &mut inst_str,
                     )?;
                     #[cfg(not(feature = "inst"))]
-                    self.process_python_line(&line, py_indent_space, &mut stream)?;
+                    self.process_python_line(&line, py_indent_prior, &mut stream)?;
                 }
                 LineType::Verilog => {
                     let line = self.apply_verilog_regex(self.escape_verilog(&line).as_str());
-                    writeln!(stream, "print(f'{line}')")?;
+                    writeln!(stream, "{}print(f'{line}')", " ".repeat(py_indent_space))?;
                 }
                 _ => {}
             }

src/inst.rs

@@ -23,7 +23,7 @@ impl Convert {
     pub(crate) fn process_python_line<W: Write>(
         &self,
         line: &str,
-        py_indent_space: usize,
+        py_indent_prior: usize,
         stream: &mut W,
         within_inst: &mut bool,
         inst_str: &mut String,
@@ -46,7 +46,7 @@ impl Convert {
                 writeln!(stream, "print('// END of INST')")?;
             }
             _ => {
-                let useful_str = utf8_slice::from(&line, py_indent_space);
+                let useful_str = utf8_slice::from(&line, py_indent_prior);
                 if *within_inst {
                     inst_str.push_str(&format!("{useful_str}\n"));
                 } else {