状態遷移図／表、すなわち設計をコードでテストする

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ラインコメント://から改行まで を抽出し出力する」

<#@ output encoding="shift_jis" #>
<#@ template debug="false" hostspecific="true" language="C#" #>
<#
   string prefix = this.Host.ResolveParameterValue("","","prefix"); 
   int slen = 0; foreach( string s in Enum.GetNames(typeof(S)) ) if ( slen < s.Length ) slen = s.Length;
   int elen = 0; foreach( string e in Enum.GetNames(typeof(E)) ) if ( elen < e.Length ) elen = e.Length;
#>
<#@ include file="state_transition_.tt" #>
<#+

    static Tuple<S,E,S[]> transition(S s, E e, params S[] n) { return Tuple.Create(s,e,n); }

    // 状態を列挙
    enum S { 
      OUT_COMMENT,
      SECOND_LEAD,
      IN_BLOCKCOMMENT,
      IN_LINECOMMENT,
      SECOND_TRAIL,
    };

    // イベントを列挙
    enum E { 
      STAR,
      SLASH,
      LF,
      OTHER
    };

    // 以下に書かれた状態遷移表に基づいてコードを生成する
    Tuple<S,E,S[]>[] _transition_ = {
      //         状態,              イベント,次の状態...
      transition(S.OUT_COMMENT,     E.STAR,  S.OUT_COMMENT),
      transition(S.OUT_COMMENT,     E.SLASH, S.SECOND_LEAD),
      transition(S.OUT_COMMENT,     E.LF,    S.OUT_COMMENT),
      transition(S.OUT_COMMENT,     E.OTHER, S.OUT_COMMENT),

      transition(S.SECOND_LEAD,     E.STAR,  S.IN_BLOCKCOMMENT),
      transition(S.SECOND_LEAD,     E.SLASH, S.IN_BLOCKCOMMENT),
      transition(S.SECOND_LEAD,     E.LF,    S.OUT_COMMENT),
      transition(S.SECOND_LEAD,     E.OTHER, S.OUT_COMMENT),

      transition(S.IN_BLOCKCOMMENT, E.STAR,  S.SECOND_TRAIL),
      transition(S.IN_BLOCKCOMMENT, E.SLASH, S.IN_BLOCKCOMMENT),
      transition(S.IN_BLOCKCOMMENT, E.LF,    S.IN_BLOCKCOMMENT),
      transition(S.IN_BLOCKCOMMENT, E.OTHER, S.IN_BLOCKCOMMENT),

      transition(S.IN_LINECOMMENT,  E.STAR,  S.IN_LINECOMMENT),
      transition(S.IN_LINECOMMENT,  E.SLASH, S.IN_LINECOMMENT),
      transition(S.IN_LINECOMMENT,  E.LF,    S.OUT_COMMENT),
      transition(S.IN_LINECOMMENT,  E.OTHER, S.IN_LINECOMMENT),

      transition(S.SECOND_TRAIL,    E.STAR,  S.SECOND_TRAIL),
      transition(S.SECOND_TRAIL,    E.SLASH, S.OUT_COMMENT),
      transition(S.SECOND_TRAIL,    E.LF,    S.IN_BLOCKCOMMENT),
      transition(S.SECOND_TRAIL,    E.OTHER, S.IN_BLOCKCOMMENT),
    };

#>

#ifndef EC_STATE_TRANSITION_H_
#define EC_STATE_TRANSITION_H_

/* -----------------------------------------------------
 * 状態遷移 ec 
 * -----------------------------------------------------
 */

#include <stdbool.h> /* from C99 : defines bool, true, false */

#include "statemachine_defs.h"

/*
 * 状態を列挙
 */
enum ec_state_code_t {
  EC_S_OUT_COMMENT,
  EC_S_SECOND_LEAD,
  EC_S_IN_BLOCKCOMMENT,
  EC_S_IN_LINECOMMENT,
  EC_S_SECOND_TRAIL,
};
typedef enum ec_state_code_t ec_state_code;
 
/*
 * イベントを列挙
 */
enum ec_event_code_t {
  EC_E_STAR,
  EC_E_SLASH,
  EC_E_LF,
  EC_E_OTHER,
};
typedef enum ec_event_code_t ec_event_code;

/*
 * イベントおよび付随するデータ
 */
struct ec_event_t {
  ec_event_code event_code_;
  /* your ftuff here */
};
typedef struct ec_event_t ec_event;

/*
 * アクションの実行に必要なデータ
 */
struct ec_context_t {
  int dummy; /* you may remove this */
  /* your stuff here */
};
typedef struct ec_context_t ec_context;

/* ---------------- */

#ifdef __cplusplus
extern "C" {
#endif

event_code  ec_event_get_event_code(const event* ev);
void        ec_event_set_event_code(event* ev, event_code evc);
void        ec_event_make(ec_event* ev, void* arg, ec_state_code st);

bool        ec_context_setup(ec_context* ctx, void* arg);
void        ec_context_teardown(ec_context* ctx);

transition* ec_state_transition_table(void);

const char* ec_state_code_to_c_str(state_code st);
const char* ec_event_code_to_c_str(event_code ev);

#ifdef __cplusplus
}
#endif

#endif

#include <assert.h>
#include <stddef.h>

#include "ec_state_transition.h"

/* -----------------------
 * state 
 * -----------------------
 */

// stcに対応する文字列を返す
const char* ec_state_code_to_c_str(state_code stc) {
  const char* result;
  switch ( stc ) {
  case EC_S_OUT_COMMENT : 
    result = "EC_S_OUT_COMMENT"; break;
  case EC_S_SECOND_LEAD : 
    result = "EC_S_SECOND_LEAD"; break;
  case EC_S_IN_BLOCKCOMMENT : 
    result = "EC_S_IN_BLOCKCOMMENT"; break;
  case EC_S_IN_LINECOMMENT : 
    result = "EC_S_IN_LINECOMMENT"; break;
  case EC_S_SECOND_TRAIL : 
    result = "EC_S_SECOND_TRAIL"; break;
  default                : 
    result = "ec_S_BAD_STATE";       break;
  }
  return result;
}

/* -----------------------
 * event 
 * -----------------------
 */

// ev内のevent_codeを返す
event_code ec_event_get_event_code(const event* ev) {
  return ((const ec_event*)ev)->event_code_;
}

// ev内にevent_codeを設定する
void       ec_event_set_event_code(event* ev, event_code evc) {
  ((ec_event*)ev)->event_code_ = evc;
}

// event_codeに対応した文字列を返す
const char* ec_event_code_to_c_str(event_code ev) {
  const char* result;
  switch ( ev ) {
  case EC_E_STAR : 
    result = "EC_E_STAR"; break;
  case EC_E_SLASH : 
    result = "EC_E_SLASH"; break;
  case EC_E_LF : 
    result = "EC_E_LF"; break;
  case EC_E_OTHER : 
    result = "EC_E_OTHER"; break;
  default      : 
    result = "EC_E_BAD_EVENT"; break;
  }
  return result;
}

// argおよびstを基に、ev内にevent_codeおよび付帯情報を設定する
void ec_event_make(ec_event* ev, void* arg, ec_state_code st) {
  /* your stuff here */
}

/* -----------------------
 * context
 * -----------------------
 */

// contextを初期化する。成功/失敗時にtrue/falseを返す。
bool ec_context_setup(ec_context* ctx, void* arg) {
  /* your stuff here */
  return true;
}

// contextを解体する。
void ec_context_teardown(ec_context* ctx) {
  /* do nothing */
}

/* -----------------------
 * action
 * -----------------------
 */

/* ec action for state:OUT_COMMENT event:STAR */
static int ec_action_S0_E0(const event* ev, context* ctx) {
  int result = 0;
#ifndef STATEMACHINE_TEST
  /* your stuff here */
#endif  
  return result;
}

... 中略 ...

/* -----------------------
 * state_transition_table
 * -----------------------
 */
transition* ec_state_transition_table(void) {
  static transition table[] = {
    { EC_S_OUT_COMMENT    , EC_E_STAR , &ec_action_S0_E0, { EC_S_OUT_COMMENT,  }},
    { EC_S_OUT_COMMENT    , EC_E_SLASH, &ec_action_S0_E1, { EC_S_SECOND_LEAD,  }},
    { EC_S_OUT_COMMENT    , EC_E_LF   , &ec_action_S0_E2, { EC_S_OUT_COMMENT,  }},
    { EC_S_OUT_COMMENT    , EC_E_OTHER, &ec_action_S0_E3, { EC_S_OUT_COMMENT,  }},
    { EC_S_SECOND_LEAD    , EC_E_STAR , &ec_action_S1_E0, { EC_S_IN_BLOCKCOMMENT,  }},
    { EC_S_SECOND_LEAD    , EC_E_SLASH, &ec_action_S1_E1, { EC_S_IN_BLOCKCOMMENT,  }},
    { EC_S_SECOND_LEAD    , EC_E_LF   , &ec_action_S1_E2, { EC_S_OUT_COMMENT,  }},
    { EC_S_SECOND_LEAD    , EC_E_OTHER, &ec_action_S1_E3, { EC_S_OUT_COMMENT,  }},
    { EC_S_IN_BLOCKCOMMENT, EC_E_STAR , &ec_action_S2_E0, { EC_S_SECOND_TRAIL,  }},
    { EC_S_IN_BLOCKCOMMENT, EC_E_SLASH, &ec_action_S2_E1, { EC_S_IN_BLOCKCOMMENT,  }},
    { EC_S_IN_BLOCKCOMMENT, EC_E_LF   , &ec_action_S2_E2, { EC_S_IN_BLOCKCOMMENT,  }},
    { EC_S_IN_BLOCKCOMMENT, EC_E_OTHER, &ec_action_S2_E3, { EC_S_IN_BLOCKCOMMENT,  }},
    { EC_S_IN_LINECOMMENT , EC_E_STAR , &ec_action_S3_E0, { EC_S_IN_LINECOMMENT,  }},
    { EC_S_IN_LINECOMMENT , EC_E_SLASH, &ec_action_S3_E1, { EC_S_IN_LINECOMMENT,  }},
    { EC_S_IN_LINECOMMENT , EC_E_LF   , &ec_action_S3_E2, { EC_S_OUT_COMMENT,  }},
    { EC_S_IN_LINECOMMENT , EC_E_OTHER, &ec_action_S3_E3, { EC_S_IN_LINECOMMENT,  }},
    { EC_S_SECOND_TRAIL   , EC_E_STAR , &ec_action_S4_E0, { EC_S_SECOND_TRAIL,  }},
    { EC_S_SECOND_TRAIL   , EC_E_SLASH, &ec_action_S4_E1, { EC_S_OUT_COMMENT,  }},
    { EC_S_SECOND_TRAIL   , EC_E_LF   , &ec_action_S4_E2, { EC_S_IN_BLOCKCOMMENT,  }},
    { EC_S_SECOND_TRAIL   , EC_E_OTHER, &ec_action_S4_E3, { EC_S_IN_BLOCKCOMMENT,  }},
    { -1, -1, NULL, { -1 }} /* DO NOT FORGET THIS TERMINATOR! */
  };
  return table;
}